refactor into racket/base

pull/5/head
Matthew Butterick 6 years ago
parent fc1e00bc2a
commit fd446e6013

@ -47,18 +47,16 @@
(define-struct tasks (active active-back waits multi-waits cache progress?))
(define-for-syntax make-token-identifier-mapping make-hasheq)
(define-for-syntax token-identifier-mapping-get
(case-lambda
[(t tok)
(hash-ref t (syntax-e tok))]
[(t tok fail)
(hash-ref t (syntax-e tok) fail)]))
(define-for-syntax token-identifier-mapping-put!
(lambda (t tok v)
(hash-set! t (syntax-e tok) v)))
(define-for-syntax token-identifier-mapping-map
(lambda (t f)
(hash-map t f)))
(define-for-syntax (token-identifier-mapping-get t tok [fail #f])
(if fail
(hash-ref t (syntax-e tok) fail)
(hash-ref t (syntax-e tok))))
(define-for-syntax (token-identifier-mapping-put! t tok v)
(hash-set! t (syntax-e tok) v))
(define-for-syntax (token-identifier-mapping-map t f)
(hash-map t f))
;; Used to calculate information on the grammar, such as whether
;; a particular non-terminal is "simple" instead of recursively defined.
@ -71,7 +69,7 @@
(cdr as) (cdr bs))]))
(let loop ()
(when (ormap-all #f
(lambda (nt pats)
(λ (nt pats)
(let ([old (bound-identifier-mapping-get nts nt)])
(let ([new (proc nt pats old)])
(if (equal? old new)
@ -88,182 +86,153 @@
(define (parse-and simple-a? parse-a parse-b
stream last-consumed-token depth end success-k fail-k
max-depth tasks)
(letrec ([mk-got-k
(lambda (success-k fail-k)
(lambda (val stream last-consumed-token depth max-depth tasks next1-k)
(if simple-a?
(parse-b val stream last-consumed-token depth end
(mk-got2-k success-k fail-k next1-k)
(mk-fail2-k success-k fail-k next1-k)
max-depth tasks)
(parallel-or
(lambda (success-k fail-k max-depth tasks)
(parse-b val stream last-consumed-token depth end
success-k fail-k
max-depth tasks))
(lambda (success-k fail-k max-depth tasks)
(next1-k (mk-got-k success-k fail-k)
fail-k max-depth tasks))
success-k fail-k max-depth tasks))))]
[mk-got2-k
(lambda (success-k fail-k next1-k)
(lambda (val stream last-consumed-token depth max-depth tasks next-k)
(success-k val stream last-consumed-token depth max-depth tasks
(lambda (success-k fail-k max-depth tasks)
(next-k (mk-got2-k success-k fail-k next1-k)
(mk-fail2-k success-k fail-k next1-k)
max-depth tasks)))))]
[mk-fail2-k
(lambda (success-k fail-k next1-k)
(lambda (max-depth tasks)
(next1-k (mk-got-k success-k fail-k)
fail-k
max-depth
tasks)))])
(parse-a stream last-consumed-token depth end
(mk-got-k success-k fail-k)
fail-k
max-depth tasks)))
(define ((mk-got-k success-k fail-k) val stream last-consumed-token depth max-depth tasks next1-k)
(if simple-a?
(parse-b val stream last-consumed-token depth end
(mk-got2-k success-k fail-k next1-k)
(mk-fail2-k success-k fail-k next1-k)
max-depth tasks)
(parallel-or
(λ (success-k fail-k max-depth tasks)
(parse-b val stream last-consumed-token depth end
success-k fail-k
max-depth tasks))
(λ (success-k fail-k max-depth tasks)
(next1-k (mk-got-k success-k fail-k)
fail-k max-depth tasks))
success-k fail-k max-depth tasks)))
(define ((mk-got2-k success-k fail-k next1-k) val stream last-consumed-token depth max-depth tasks next-k)
(success-k val stream last-consumed-token depth max-depth tasks
(λ (success-k fail-k max-depth tasks)
(next-k (mk-got2-k success-k fail-k next1-k)
(mk-fail2-k success-k fail-k next1-k)
max-depth tasks))))
(define ((mk-fail2-k success-k fail-k next1-k) max-depth tasks)
(next1-k (mk-got-k success-k fail-k) fail-k max-depth tasks))
(parse-a stream last-consumed-token depth end
(mk-got-k success-k fail-k)
fail-k
max-depth tasks))
;; Parallel or for non-terminal alternatives
(define (parse-parallel-or parse-a parse-b stream last-consumed-token depth end success-k fail-k max-depth tasks)
(parallel-or (lambda (success-k fail-k max-depth tasks)
(parallel-or (λ (success-k fail-k max-depth tasks)
(parse-a stream last-consumed-token depth end success-k fail-k max-depth tasks))
(lambda (success-k fail-k max-depth tasks)
(λ (success-k fail-k max-depth tasks)
(parse-b stream last-consumed-token depth end success-k fail-k max-depth tasks))
success-k fail-k max-depth tasks))
;; Generic parallel-or
(define (parallel-or parse-a parse-b success-k fail-k max-depth tasks)
(define answer-key (gensym))
(letrec ([gota-k
(lambda (val stream last-consumed-token depth max-depth tasks next-k)
(report-answer answer-key
max-depth
tasks
(list val stream last-consumed-token depth next-k)))]
[faila-k
(lambda (max-depth tasks)
(report-answer answer-key
max-depth
tasks
null))])
(let* ([tasks (queue-task
(define (gota-k val stream last-consumed-token depth max-depth tasks next-k)
(report-answer answer-key
max-depth
tasks
(list val stream last-consumed-token depth next-k)))
(define (faila-k max-depth tasks)
(report-answer answer-key
max-depth
tasks
(lambda (max-depth tasks)
(parse-a gota-k
faila-k
max-depth tasks)))]
[tasks (queue-task
null))
(let* ([tasks (queue-task tasks (λ (max-depth tasks)
(parse-a gota-k faila-k max-depth tasks)))]
[tasks (queue-task tasks (λ (max-depth tasks)
(parse-b gota-k faila-k max-depth tasks)))]
[queue-next (λ (next-k tasks)
(queue-task tasks (λ (max-depth tasks)
(next-k gota-k faila-k max-depth tasks))))])
(define ((mk-got-one immediate-next? get-nth success-k) val stream last-consumed-token depth max-depth tasks next-k)
(let ([tasks (if immediate-next?
(queue-next next-k tasks)
tasks)])
(success-k val stream last-consumed-token depth max-depth
tasks
(lambda (max-depth tasks)
(parse-b gota-k
faila-k
max-depth tasks)))]
[queue-next (lambda (next-k tasks)
(queue-task tasks
(lambda (max-depth tasks)
(next-k gota-k
faila-k
max-depth tasks))))])
(letrec ([mk-got-one
(lambda (immediate-next? get-nth success-k)
(lambda (val stream last-consumed-token depth max-depth tasks next-k)
(let ([tasks (if immediate-next?
(queue-next next-k tasks)
tasks)])
(success-k val stream last-consumed-token depth max-depth
tasks
(lambda (success-k fail-k max-depth tasks)
(let ([tasks (if immediate-next?
tasks
(queue-next next-k tasks))])
(get-nth max-depth tasks success-k fail-k)))))))]
[get-first
(lambda (max-depth tasks success-k fail-k)
(wait-for-answer #f max-depth tasks answer-key
(mk-got-one #t get-first success-k)
(lambda (max-depth tasks)
(get-second max-depth tasks success-k fail-k))
#f))]
[get-second
(lambda (max-depth tasks success-k fail-k)
(wait-for-answer #f max-depth tasks answer-key
(mk-got-one #f get-second success-k)
fail-k #f))])
(get-first max-depth tasks success-k fail-k)))))
(λ (success-k fail-k max-depth tasks)
(let ([tasks (if immediate-next?
tasks
(queue-next next-k tasks))])
(get-nth max-depth tasks success-k fail-k))))))
(define (get-first max-depth tasks success-k fail-k)
(wait-for-answer #f max-depth tasks answer-key
(mk-got-one #t get-first success-k)
(λ (max-depth tasks)
(get-second max-depth tasks success-k fail-k))
#f))
(define (get-second max-depth tasks success-k fail-k)
(wait-for-answer #f max-depth tasks answer-key
(mk-got-one #f get-second success-k)
fail-k #f))
(get-first max-depth tasks success-k fail-k)))
;; Non-terminal alternatives where the first is "simple" can be done
;; sequentially, which is simpler
(define (parse-or parse-a parse-b
stream last-consumed-token depth end success-k fail-k max-depth tasks)
(letrec ([mk-got-k
(lambda (success-k fail-k)
(lambda (val stream last-consumed-token depth max-depth tasks next-k)
(success-k val stream last-consumed-token depth
max-depth tasks
(lambda (success-k fail-k max-depth tasks)
(next-k (mk-got-k success-k fail-k)
(mk-fail-k success-k fail-k)
max-depth tasks)))))]
[mk-fail-k
(lambda (success-k fail-k)
(lambda (max-depth tasks)
(parse-b stream last-consumed-token depth end success-k fail-k max-depth tasks)))])
(parse-a stream last-consumed-token depth end
(mk-got-k success-k fail-k)
(mk-fail-k success-k fail-k)
max-depth tasks)))
(define ((mk-got-k success-k fail-k) val stream last-consumed-token depth max-depth tasks next-k)
(success-k val stream last-consumed-token depth
max-depth tasks
(λ (success-k fail-k max-depth tasks)
(next-k (mk-got-k success-k fail-k)
(mk-fail-k success-k fail-k)
max-depth tasks))))
(define ((mk-fail-k success-k fail-k) max-depth tasks)
(parse-b stream last-consumed-token depth end success-k fail-k max-depth tasks))
(parse-a stream last-consumed-token depth end
(mk-got-k success-k fail-k)
(mk-fail-k success-k fail-k)
max-depth tasks))
;; Starts a thread
(define queue-task
(lambda (tasks t [progress? #t])
(make-tasks (tasks-active tasks)
(cons t (tasks-active-back tasks))
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
(or progress? (tasks-progress? tasks)))))
(define (queue-task tasks t [progress? #t])
(make-tasks (tasks-active tasks)
(cons t (tasks-active-back tasks))
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
(or progress? (tasks-progress? tasks))))
;; Reports an answer to a waiting thread:
(define (report-answer answer-key max-depth tasks val)
(let ([v (hash-ref (tasks-waits tasks) answer-key (lambda () #f))])
(if v
(let ([tasks (make-tasks (cons (v val)
(tasks-active tasks))
(tasks-active-back tasks)
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
#t)])
(hash-remove! (tasks-waits tasks) answer-key)
(swap-task max-depth tasks))
;; We have an answer ready too fast; wait
(swap-task max-depth
(queue-task tasks
(lambda (max-depth tasks)
(report-answer answer-key max-depth tasks val))
#f)))))
(define v (hash-ref (tasks-waits tasks) answer-key (λ () #f)))
(if v
(let ([tasks (make-tasks (cons (v val) (tasks-active tasks))
(tasks-active-back tasks)
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
#t)])
(hash-remove! (tasks-waits tasks) answer-key)
(swap-task max-depth tasks))
;; We have an answer ready too fast; wait
(swap-task max-depth
(queue-task tasks
(λ (max-depth tasks)
(report-answer answer-key max-depth tasks val))
#f))))
;; Reports an answer to multiple waiting threads:
(define (report-answer-all answer-key max-depth tasks val k)
(let ([v (hash-ref (tasks-multi-waits tasks) answer-key (lambda () null))])
(hash-remove! (tasks-multi-waits tasks) answer-key)
(let ([tasks (make-tasks (append (map (lambda (a) (a val)) v)
(tasks-active tasks))
(tasks-active-back tasks)
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
#t)])
(k max-depth tasks))))
(define v (hash-ref (tasks-multi-waits tasks) answer-key (λ () null)))
(hash-remove! (tasks-multi-waits tasks) answer-key)
(let ([tasks (make-tasks (append (map (λ (a) (a val)) v)
(tasks-active tasks))
(tasks-active-back tasks)
(tasks-waits tasks)
(tasks-multi-waits tasks)
(tasks-cache tasks)
#t)])
(k max-depth tasks)))
;; Waits for an answer; if `multi?' is #f, this is sole waiter, otherwise
;; there might be many. Use wither #t or #f (and `report-answer' or
;; `report-answer-all', resptively) consistently for a particular answer key.
(define (wait-for-answer multi? max-depth tasks answer-key success-k fail-k deadlock-k)
(let ([wait (lambda (val)
(lambda (max-depth tasks)
(let ([wait (λ (val)
(λ (max-depth tasks)
(if val
(if (null? val)
(fail-k max-depth tasks)
@ -273,7 +242,7 @@
(if multi?
(hash-set! (tasks-multi-waits tasks) answer-key
(cons wait (hash-ref (tasks-multi-waits tasks) answer-key
(lambda () null))))
(λ () null))))
(hash-set! (tasks-waits tasks) answer-key wait))
(let ([tasks (make-tasks (tasks-active tasks)
(tasks-active-back tasks)
@ -302,8 +271,8 @@
(make-tasks (apply
append
(hash-map (tasks-multi-waits tasks)
(lambda (k l)
(map (lambda (v) (v #f)) l))))
(λ (k l)
(map (λ (v) (v #f)) l))))
(tasks-active-back tasks)
(tasks-waits tasks)
(make-hasheq)
@ -325,11 +294,9 @@
(define no-pos-val (make-position #f #f #f))
(define-for-syntax no-pos
(let ([npv ((syntax-local-certifier) #'no-pos-val)])
(lambda (stx) npv)))
(define-for-syntax at-tok-pos
(lambda (sel expr)
(lambda (stx)
#`(let ([v #,expr]) (if v (#,sel v) no-pos-val)))))
(λ (stx) npv)))
(define-for-syntax ((at-tok-pos sel expr) stx)
#`(let ([v #,expr]) (if v (#,sel v) no-pos-val)))
;; Builds a matcher for a particular alternative
(define-for-syntax (build-match nts toks pat handle $ctx)
@ -337,27 +304,23 @@
[pos 1])
(if (null? pat)
#`(success-k #,handle stream last-consumed-token depth max-depth tasks
(lambda (success-k fail-k max-depth tasks)
(λ (success-k fail-k max-depth tasks)
(fail-k max-depth tasks)))
(let ([id (datum->syntax (car pat)
(string->symbol (format "$~a" pos)))]
[id-start-pos (datum->syntax (car pat)
(string->symbol (format "$~a-start-pos" pos)))]
[id-end-pos (datum->syntax (car pat)
(string->symbol (format "$~a-end-pos" pos)))]
[n-end-pos (and (null? (cdr pat))
(datum->syntax (car pat) '$n-end-pos))])
(let ([id (datum->syntax (car pat) (string->symbol (format "$~a" pos)))]
[id-start-pos (datum->syntax (car pat) (string->symbol (format "$~a-start-pos" pos)))]
[id-end-pos (datum->syntax (car pat) (string->symbol (format "$~a-end-pos" pos)))]
[n-end-pos (and (null? (cdr pat)) (datum->syntax (car pat) '$n-end-pos))])
(cond
[(bound-identifier-mapping-get nts (car pat) (lambda () #f))
[(bound-identifier-mapping-get nts (car pat) (λ () #f))
;; Match non-termimal
#`(parse-and
;; First part is simple? (If so, we don't have to parallelize the `and'.)
#,(let ([l (bound-identifier-mapping-get nts (car pat) (lambda () #f))])
#,(let ([l (bound-identifier-mapping-get nts (car pat) (λ () #f))])
(or (not l)
(andmap values (caddr l))))
#,(car pat)
(let ([original-stream stream])
(lambda (#,id stream last-consumed-token depth end success-k fail-k max-depth tasks)
(λ (#,id stream last-consumed-token depth end success-k fail-k max-depth tasks)
(let-syntax ([#,id-start-pos (at-tok-pos #'(if (eq? original-stream stream)
tok-end
tok-start)
@ -372,10 +335,10 @@
#,(loop (cdr pat) (add1 pos)))))
stream last-consumed-token depth
#,(let ([cnt (apply +
(map (lambda (item)
(map (λ (item)
(cond
[(bound-identifier-mapping-get nts item (lambda () #f))
=> (lambda (l) (car l))]
[(bound-identifier-mapping-get nts item (λ () #f))
=> (λ (l) (car l))]
[else 1]))
(cdr pat)))])
#`(- end #,cnt))
@ -419,75 +382,73 @@
[max-depth max-depth]
[tasks tasks]
[k k])
(let ([answer-key (gensym)]
[table-key (vector key depth n)]
[old-depth depth]
[old-stream stream])
#;(printf "Loop ~a\n" table-key)
(cond
[(hash-ref (tasks-cache tasks) table-key (lambda () #f))
=> (lambda (result)
#;(printf "Reuse ~a\n" table-key)
(result success-k fail-k max-depth tasks))]
[else
#;(printf "Try ~a ~a\n" table-key (map tok-name stream))
(hash-set! (tasks-cache tasks) table-key
(lambda (success-k fail-k max-depth tasks)
#;(printf "Wait ~a ~a\n" table-key answer-key)
(wait-for-answer #t max-depth tasks answer-key success-k fail-k
(lambda (max-depth tasks)
#;(printf "Deadlock ~a ~a\n" table-key answer-key)
(fail-k max-depth tasks)))))
(let result-loop ([max-depth max-depth][tasks tasks][k k])
(letrec ([orig-stream stream]
[new-got-k
(lambda (val stream last-consumed-token depth max-depth tasks next-k)
;; Check whether we already have a result that consumed the same amount:
(let ([result-key (vector #f key old-depth depth)])
(cond
[(hash-ref (tasks-cache tasks) result-key (lambda () #f))
;; Go for the next-result
(result-loop max-depth
tasks
(lambda (end max-depth tasks success-k fail-k)
(next-k success-k fail-k max-depth tasks)))]
[else
#;(printf "Success ~a ~a\n" table-key
(map tok-name (let loop ([d old-depth][s old-stream])
(if (= d depth)
null
(cons (car s) (loop (add1 d) (cdr s)))))))
(let ([next-k (lambda (success-k fail-k max-depth tasks)
(loop (add1 n)
success-k
fail-k
max-depth
tasks
(lambda (end max-depth tasks success-k fail-k)
(next-k success-k fail-k max-depth tasks))))])
(hash-set! (tasks-cache tasks) result-key #t)
(hash-set! (tasks-cache tasks) table-key
(lambda (success-k fail-k max-depth tasks)
(success-k val stream last-consumed-token depth max-depth tasks next-k)))
(report-answer-all answer-key
max-depth
tasks
(list val stream last-consumed-token depth next-k)
(lambda (max-depth tasks)
(success-k val stream last-consumed-token depth max-depth tasks next-k))))])))]
[new-fail-k
(lambda (max-depth tasks)
#;(printf "Failure ~a\n" table-key)
(hash-set! (tasks-cache tasks) table-key
(lambda (success-k fail-k max-depth tasks)
(fail-k max-depth tasks)))
(report-answer-all answer-key
max-depth
tasks
null
(lambda (max-depth tasks)
(fail-k max-depth tasks))))])
(k end max-depth tasks new-got-k new-fail-k)))])))))
(define answer-key (gensym))
(define table-key (vector key depth n))
(define old-depth depth)
(define old-stream stream)
#;(printf "Loop ~a\n" table-key)
(cond
[(hash-ref (tasks-cache tasks) table-key (λ () #f))
=> (λ (result)
#;(printf "Reuse ~a\n" table-key)
(result success-k fail-k max-depth tasks))]
[else
#;(printf "Try ~a ~a\n" table-key (map tok-name stream))
(hash-set! (tasks-cache tasks) table-key
(λ (success-k fail-k max-depth tasks)
#;(printf "Wait ~a ~a\n" table-key answer-key)
(wait-for-answer #t max-depth tasks answer-key success-k fail-k
(λ (max-depth tasks)
#;(printf "Deadlock ~a ~a\n" table-key answer-key)
(fail-k max-depth tasks)))))
(let result-loop ([max-depth max-depth][tasks tasks][k k])
(define orig-stream stream)
(define (new-got-k val stream last-consumed-token depth max-depth tasks next-k)
;; Check whether we already have a result that consumed the same amount:
(define result-key (vector #f key old-depth depth))
(cond
[(hash-ref (tasks-cache tasks) result-key (λ () #f))
;; Go for the next-result
(result-loop max-depth
tasks
(λ (end max-depth tasks success-k fail-k)
(next-k success-k fail-k max-depth tasks)))]
[else
#;(printf "Success ~a ~a\n" table-key
(map tok-name (let loop ([d old-depth][s old-stream])
(if (= d depth)
null
(cons (car s) (loop (add1 d) (cdr s)))))))
(let ([next-k (λ (success-k fail-k max-depth tasks)
(loop (add1 n)
success-k
fail-k
max-depth
tasks
(λ (end max-depth tasks success-k fail-k)
(next-k success-k fail-k max-depth tasks))))])
(hash-set! (tasks-cache tasks) result-key #t)
(hash-set! (tasks-cache tasks) table-key
(λ (success-k fail-k max-depth tasks)
(success-k val stream last-consumed-token depth max-depth tasks next-k)))
(report-answer-all answer-key
max-depth
tasks
(list val stream last-consumed-token depth next-k)
(λ (max-depth tasks)
(success-k val stream last-consumed-token depth max-depth tasks next-k))))]))
(define (new-fail-k max-depth tasks)
#;(printf "Failure ~a\n" table-key)
(hash-set! (tasks-cache tasks) table-key
(λ (success-k fail-k max-depth tasks)
(fail-k max-depth tasks)))
(report-answer-all answer-key
max-depth
tasks
null
(λ (max-depth tasks)
(fail-k max-depth tasks))))
(k end max-depth tasks new-got-k new-fail-k))]))))
;; These temp identifiers can't be `gensym` or `generate-temporary`
;; because they have to be consistent between module loads
@ -497,39 +458,34 @@
(define-for-syntax atok-id-temp 'atok_wrutdjgecmybyfipiwsgjlvsveryodlgassuzcargiuznzgdghrykfqfbwcjgzdhdoeqxcucmtjkuyucskzethozhqkasphdwbht)
(define-syntax (cfg-parser stx)
(syntax-case stx ()
[(_ clause ...)
(let ([clauses (syntax->list #'(clause ...))])
[(_ CLAUSE ...)
(let ([clauses (syntax->list #'(CLAUSE ...))])
(let-values ([(start grammar cfg-error parser-clauses src-pos?)
(let ([all-toks (apply
append
(map (lambda (clause)
(syntax-case clause (tokens)
[(tokens t ...)
(apply
append
(map (lambda (t)
(let ([v (syntax-local-value t (lambda () #f))])
(cond
[(terminals-def? v)
(map (lambda (v)
(cons v #f))
(syntax->list (terminals-def-t v)))]
[(e-terminals-def? v)
(map (lambda (v)
(cons v #t))
(syntax->list (e-terminals-def-t v)))]
[else null])))
(syntax->list #'(t ...))))]
[_else null]))
clauses))]
(for/list ([clause (in-list clauses)])
(syntax-case clause (tokens)
[(tokens T ...)
(apply
append
(for/list ([t (in-list (syntax->list #'(T ...)))])
(define v (syntax-local-value t (λ () #f)))
(cond
[(terminals-def? v)
(for/list ([v (in-list (syntax->list (terminals-def-t v)))])
(cons v #f))]
[(e-terminals-def? v)
(for/list ([v (in-list (syntax->list (e-terminals-def-t v)))])
(cons v #t))]
[else null])))]
[_else null])))]
[all-end-toks (apply
append
(map (lambda (clause)
(syntax-case clause (end)
[(end t ...)
(syntax->list #'(t ...))]
[_else null]))
clauses))])
(for/list ([clause (in-list clauses)])
(syntax-case clause (end)
[(end T ...)
(syntax->list #'(T ...))]
[_else null])))])
(let loop ([clauses clauses]
[cfg-start #f]
[cfg-grammar #f]
@ -543,47 +499,35 @@
(reverse parser-clauses)
src-pos?)
(syntax-case (car clauses) (start error grammar src-pos)
[(start tok)
(loop (cdr clauses) #'tok cfg-grammar cfg-error src-pos? parser-clauses)]
[(error expr)
(loop (cdr clauses) cfg-start cfg-grammar #'expr src-pos? parser-clauses)]
[(grammar [nt [pat handle0 handle ...] ...] ...)
[(start TOK)
(loop (cdr clauses) #'TOK cfg-grammar cfg-error src-pos? parser-clauses)]
[(error EXPR)
(loop (cdr clauses) cfg-start cfg-grammar #'EXPR src-pos? parser-clauses)]
[(grammar [NT [PAT HANDLE0 HANDLE ...] ...] ...)
(let ([nts (make-bound-identifier-mapping)]
[toks (make-token-identifier-mapping)]
[end-toks (make-token-identifier-mapping)]
[nt-ids (syntax->list #'(nt ...))]
[patss (map (lambda (stx)
[nt-ids (syntax->list #'(NT ...))]
[patss (map (λ (stx)
(map syntax->list (syntax->list stx)))
(syntax->list #'((pat ...) ...)))])
(for-each (lambda (nt)
(bound-identifier-mapping-put! nts nt (list 0)))
nt-ids)
(for-each (lambda (t)
(token-identifier-mapping-put! end-toks t #t))
all-end-toks)
(for-each (lambda (t)
(unless (token-identifier-mapping-get end-toks (car t) (lambda () #f))
(let ([id (gensym (syntax-e (car t)))])
(token-identifier-mapping-put! toks (car t)
(cons id (cdr t))))))
all-toks)
(syntax->list #'((PAT ...) ...)))])
(for ([nt (in-list nt-ids)])
(bound-identifier-mapping-put! nts nt (list 0)))
(for ([t (in-list all-end-toks)])
(token-identifier-mapping-put! end-toks t #t))
(for ([t (in-list all-toks)]
#:unless (token-identifier-mapping-get end-toks (car t) (λ () #f)))
(define id (gensym (syntax-e (car t))))
(token-identifier-mapping-put! toks (car t) (cons id (cdr t))))
;; Compute min max size for each non-term:
(nt-fixpoint
nts
(lambda (nt pats old-list)
(λ (nt pats old-list)
(let ([new-cnt
(apply
min
(map (lambda (pat)
(apply
+
(map (lambda (elem)
(car
(bound-identifier-mapping-get nts
elem
(lambda () (list 1)))))
pat)))
pats))])
(apply min (for/list ([pat (in-list pats)])
(for/sum ([elem (in-list pat)])
(car (bound-identifier-mapping-get
nts elem (λ () (list 1)))))))])
(if (new-cnt . > . (car old-list))
(cons new-cnt (cdr old-list))
old-list)))
@ -592,29 +536,28 @@
;; for a non-terminal
(nt-fixpoint
nts
(lambda (nt pats old-list)
(λ (nt pats old-list)
(let ([new-list
(apply
append
(map (lambda (pat)
(let loop ([pat pat])
(if (pair? pat)
(let ([l (bound-identifier-mapping-get
nts
(car pat)
(lambda ()
(list 1 (map-token toks (car pat)))))])
;; If the non-terminal can match 0 things,
;; then it might match something from the
;; next pattern element. Otherwise, it must
;; match the first element:
(if (zero? (car l))
(append (cdr l) (loop (cdr pat)))
(cdr l)))
null)))
pats))])
(let ([new (filter (lambda (id)
(andmap (lambda (id2)
(for/list ([pat (in-list pats)])
(let loop ([pat pat])
(if (pair? pat)
(let ([l (bound-identifier-mapping-get
nts
(car pat)
(λ ()
(list 1 (map-token toks (car pat)))))])
;; If the non-terminal can match 0 things,
;; then it might match something from the
;; next pattern element. Otherwise, it must
;; match the first element:
(if (zero? (car l))
(append (cdr l) (loop (cdr pat)))
(cdr l)))
null))))])
(let ([new (filter (λ (id)
(andmap (λ (id2)
(not (eq? id id2)))
(cdr old-list)))
new-list)])
@ -623,7 +566,7 @@
(let ([new (let loop ([new new])
(if (null? (cdr new))
new
(if (ormap (lambda (id)
(if (ormap (λ (id)
(eq? (car new) id))
(cdr new))
(loop (cdr new))
@ -632,26 +575,26 @@
old-list))))
nt-ids patss)
;; Determine left-recursive clauses:
(for-each (lambda (nt pats)
(for-each (λ (nt pats)
(let ([l (bound-identifier-mapping-get nts nt)])
(bound-identifier-mapping-put! nts nt (list (car l)
(cdr l)
(map (lambda (x) #f) pats)))))
(map (λ (x) #f) pats)))))
nt-ids patss)
(nt-fixpoint
nts
(lambda (nt pats old-list)
(λ (nt pats old-list)
(list (car old-list)
(cadr old-list)
(map (lambda (pat simple?)
(map (λ (pat simple?)
(or simple?
(let ([l (map (lambda (elem)
(let ([l (map (λ (elem)
(bound-identifier-mapping-get
nts
elem
(lambda () #f)))
(λ () #f)))
pat)])
(andmap (lambda (i)
(andmap (λ (i)
(or (not i)
(andmap values (caddr i))))
l))))
@ -660,16 +603,16 @@
;; Build a definition for each non-term:
(loop (cdr clauses)
cfg-start
(map (lambda (nt pats handles $ctxs)
(map (λ (nt pats handles $ctxs)
(define info (bound-identifier-mapping-get nts nt))
(list nt
#`(let ([key (gensym '#,nt)])
(lambda (stream last-consumed-token depth end success-k fail-k max-depth tasks)
(λ (stream last-consumed-token depth end success-k fail-k max-depth tasks)
(parse-nt/share
key #,(car info) '#,(cadr info) stream last-consumed-token depth end
max-depth tasks
success-k fail-k
(lambda (end max-depth tasks success-k fail-k)
(λ (end max-depth tasks success-k fail-k)
#,(let loop ([pats pats]
[handles (syntax->list handles)]
[$ctxs (syntax->list $ctxs)]
@ -680,13 +623,13 @@
(car simple?s))
#'parse-or
#'parse-parallel-or)
(lambda (stream last-consumed-token depth end success-k fail-k max-depth tasks)
(λ (stream last-consumed-token depth end success-k fail-k max-depth tasks)
#,(build-match nts
toks
(car pats)
(car handles)
(car $ctxs)))
(lambda (stream last-consumed-token depth end success-k fail-k max-depth tasks)
(λ (stream last-consumed-token depth end success-k fail-k max-depth tasks)
#,(loop (cdr pats)
(cdr handles)
(cdr $ctxs)
@ -694,14 +637,14 @@
stream last-consumed-token depth end success-k fail-k max-depth tasks)))))))))
nt-ids
patss
(syntax->list #'(((begin handle0 handle ...) ...) ...))
(syntax->list #'((handle0 ...) ...)))
(syntax->list #'(((begin HANDLE0 HANDLE ...) ...) ...))
(syntax->list #'((HANDLE0 ...) ...)))
cfg-error
src-pos?
(list*
(with-syntax ([((tok tok-id . $e) ...)
(token-identifier-mapping-map toks
(lambda (k v)
(λ (k v)
(list* k
(car v)
(if (cdr v)
@ -743,19 +686,19 @@
src-pos?
(cons (car clauses) parser-clauses))]))))])
#`(let ([orig-parse (parser
[error (lambda (a b c)
[error (λ (a b c)
(error 'cfg-parser "unexpected ~a token: ~a" b c))]
. #,parser-clauses)]
[error-proc #,cfg-error])
(letrec #,grammar
(lambda (get-tok)
(λ (get-tok)
(let ([tok-list (orig-parse get-tok)])
(letrec ([success-k
(lambda (val stream last-consumed-token depth max-depth tasks next)
(λ (val stream last-consumed-token depth max-depth tasks next)
(if (null? stream)
val
(next success-k fail-k max-depth tasks)))]
[fail-k (lambda (max-depth tasks)
[fail-k (λ (max-depth tasks)
(cond
[(null? tok-list)
(if error-proc
@ -847,7 +790,7 @@
(define (parse s)
(define ip (open-input-string s))
(port-count-lines! ip)
(-parse (lambda () (lex ip))))
(-parse (λ () (lex ip))))
(check-equal? (parse "abc")
'(unanchored (lit "abc" 1 4) 1 4))
@ -881,7 +824,7 @@
(tokens non-terminals)
(start <program>)
(end EOF)
(error (lambda (a b stx)
(error (λ (a b stx)
(error 'parse "failed at ~s" stx)))
(grammar [<program> [(PLUS) "plus"]
[(<minus-program> BAR <minus-program>) (list $1 $2 $3)]
@ -903,7 +846,7 @@
-|-*|-|-**|-|-*|-|-***|-|-*|-|-**|-|-*|-|-*****"
;; This one fails:
#;"+*")])
(check-equal? (parse (lambda () (lex p)))
(check-equal? (parse (λ () (lex p)))
'((((((((((("minus" || "minus") . *) || (("minus" || "minus") . *)) . *) || (((("minus" || "minus") . *) || (("minus" || "minus") . *)) . *)) . *)
||
(((((("minus" || "minus") . *) || (("minus" || "minus") . *)) . *) || (((("minus" || "minus") . *) || (("minus" || "minus") . *)) . *)) . *))

@ -1,4 +1,4 @@
#lang scheme
#lang racket/base
;; An interactive calculator inspired by the calculator example in the bison manual.
@ -15,19 +15,19 @@
(define vars (make-hash))
(define-lex-abbrevs
(lower-letter (:/ "a" "z"))
(lower-letter (:/ "a" "z"))
(upper-letter (:/ #\A #\Z))
(upper-letter (:/ #\A #\Z))
;; (:/ 0 9) would not work because the lexer does not understand numbers. (:/ #\0 #\9) is ok too.
(digit (:/ "0" "9")))
;; (:/ 0 9) would not work because the lexer does not understand numbers. (:/ #\0 #\9) is ok too.
(digit (:/ "0" "9")))
(define calcl
(define calc-lex
(lexer
[(eof) 'EOF]
;; recursively call the lexer on the remaining input after a tab or space. Returning the
;; result of that operation. This effectively skips all whitespace.
[(:or #\tab #\space) (calcl input-port)]
[(:or #\tab #\space) (calc-lex input-port)]
;; (token-newline) returns 'newline
[#\newline (token-newline)]
;; Since (token-=) returns '=, just return the symbol directly
@ -40,7 +40,7 @@
[(:: (:+ digit) #\. (:* digit)) (token-NUM (string->number lexeme))]))
(define calcp
(define calc-parse
(parser
(start start)
@ -78,12 +78,15 @@
;; run the calculator on the given input-port
(define (calc ip)
(port-count-lines! ip)
(letrec ((one-line
(lambda ()
(let ((result (calcp (lambda () (calcl ip)))))
(when result
(printf "~a\n" result)
(one-line))))))
(one-line)))
(let loop ()
(define result (calc-parse (λ () (calc-lex ip))))
(when result
(printf "~a\n" result)
(loop))))
(calc (open-input-string "x=1\n(x + 2 * 3) - (1+2)*3"))
(module+ test
(require rackunit)
(check-equal? (let ([o (open-output-string)])
(parameterize ([current-output-port o])
(calc (open-input-string "x=1\n(x + 2 * 3) - (1+2)*3")))
(get-output-string o)) "1\n-2\n"))

@ -1,242 +1,240 @@
#lang racket/base
;; This implements the equivalent of racket's read-syntax for R5RS scheme.
;; It has not been thoroughly tested. Also it will read an entire file into a
;; list of syntax objects, instead of returning one syntax object at a time
(module read mzscheme
(require br-parser-tools/lex
(prefix : br-parser-tools/lex-sre)
br-parser-tools/yacc
syntax/readerr)
(require (for-syntax racket/base)
br-parser-tools/lex
(prefix-in : br-parser-tools/lex-sre)
br-parser-tools/yacc
syntax/readerr)
(define-tokens data (DATUM))
(define-empty-tokens delim (OP CP HASHOP QUOTE QUASIQUOTE UNQUOTE UNQUOTE-SPLICING DOT EOF))
(define-tokens data (DATUM))
(define-empty-tokens delim (OP CP HASHOP QUOTE QUASIQUOTE UNQUOTE UNQUOTE-SPLICING DOT EOF))
(define scheme-lexer
(lexer-src-pos
(define scheme-lexer
(lexer-src-pos
;; Skip comments, without accumulating extra position information
[(:or scheme-whitespace comment) (return-without-pos (scheme-lexer input-port))]
;; Skip comments, without accumulating extra position information
[(:or scheme-whitespace comment) (return-without-pos (scheme-lexer input-port))]
["#t" (token-DATUM #t)]
["#f" (token-DATUM #f)]
[(:: "#\\" any-char) (token-DATUM (caddr (string->list lexeme)))]
["#\\space" (token-DATUM #\space)]
["#\\newline" (token-DATUM #\newline)]
[(:or (:: initial (:* subsequent)) "+" "-" "...") (token-DATUM (string->symbol lexeme))]
[#\" (token-DATUM (list->string (get-string-token input-port)))]
[#\( 'OP]
[#\) 'CP]
[#\[ 'OP]
[#\] 'CP]
["#(" 'HASHOP]
[num2 (token-DATUM (string->number lexeme 2))]
[num8 (token-DATUM (string->number lexeme 8))]
[num10 (token-DATUM (string->number lexeme 10))]
[num16 (token-DATUM (string->number lexeme 16))]
["'" 'QUOTE]
["`" 'QUASIQUOTE]
["," 'UNQUOTE]
[",@" 'UNQUOTE-SPLICING]
["." 'DOT]
[(eof) 'EOF]))
["#t" (token-DATUM #t)]
["#f" (token-DATUM #f)]
[(:: "#\\" any-char) (token-DATUM (caddr (string->list lexeme)))]
["#\\space" (token-DATUM #\space)]
["#\\newline" (token-DATUM #\newline)]
[(:or (:: initial (:* subsequent)) "+" "-" "...") (token-DATUM (string->symbol lexeme))]
[#\" (token-DATUM (list->string (get-string-token input-port)))]
[#\( 'OP]
[#\) 'CP]
[#\[ 'OP]
[#\] 'CP]
["#(" 'HASHOP]
[num2 (token-DATUM (string->number lexeme 2))]
[num8 (token-DATUM (string->number lexeme 8))]
[num10 (token-DATUM (string->number lexeme 10))]
[num16 (token-DATUM (string->number lexeme 16))]
["'" 'QUOTE]
["`" 'QUASIQUOTE]
["," 'UNQUOTE]
[",@" 'UNQUOTE-SPLICING]
["." 'DOT]
[(eof) 'EOF]))
(define get-string-token
(lexer
[(:~ #\" #\\) (cons (car (string->list lexeme))
(get-string-token input-port))]
[(:: #\\ #\\) (cons #\\ (get-string-token input-port))]
[(:: #\\ #\") (cons #\" (get-string-token input-port))]
[#\" null]))
(define get-string-token
(lexer
[(:~ #\" #\\) (cons (car (string->list lexeme))
(get-string-token input-port))]
[(:: #\\ #\\) (cons #\\ (get-string-token input-port))]
[(:: #\\ #\") (cons #\" (get-string-token input-port))]
[#\" null]))
(define-lex-abbrevs
[letter (:or (:/ "a" "z") (:/ #\A #\Z))]
[digit (:/ #\0 #\9)]
[scheme-whitespace (:or #\newline #\return #\tab #\space #\vtab)]
[initial (:or letter (char-set "!$%&*/:<=>?^_~@"))]
[subsequent (:or initial digit (char-set "+-.@"))]
[comment (:: #\; (:* (:~ #\newline)) #\newline)]
(define-lex-abbrevs
[letter (:or (:/ "a" "z") (:/ #\A #\Z))]
[digit (:/ #\0 #\9)]
[scheme-whitespace (:or #\newline #\return #\tab #\space #\vtab)]
[initial (:or letter (char-set "!$%&*/:<=>?^_~@"))]
[subsequent (:or initial digit (char-set "+-.@"))]
[comment (:: #\; (:* (:~ #\newline)) #\newline)]
;; See ${PLTHOME}/collects/syntax-color/racket-lexer.rkt for an example of
;; using regexp macros to avoid the cut and paste.
; [numR (:: prefixR complexR)]
; [complexR (:or realR
; (:: realR "@" realR)
; (:: realR "+" urealR "i")
; (:: realR "-" urealR "i")
; (:: realR "+i")
; (:: realR "-i")
; (:: "+" urealR "i")
; (:: "-" urealR "i")
; (:: "+i")
; (:: "-i"))]
; [realR (:: sign urealR)]
; [urealR (:or uintegerR (:: uintegerR "/" uintegerR) decimalR)]
; [uintegerR (:: (:+ digitR) (:* #\#))]
; [prefixR (:or (:: radixR exactness)
; (:: exactness radixR))]
;; See ${PLTHOME}/collects/syntax-color/racket-lexer.rkt for an example of
;; using regexp macros to avoid the cut and paste.
; [numR (:: prefixR complexR)]
; [complexR (:or realR
; (:: realR "@" realR)
; (:: realR "+" urealR "i")
; (:: realR "-" urealR "i")
; (:: realR "+i")
; (:: realR "-i")
; (:: "+" urealR "i")
; (:: "-" urealR "i")
; (:: "+i")
; (:: "-i"))]
; [realR (:: sign urealR)]
; [urealR (:or uintegerR (:: uintegerR "/" uintegerR) decimalR)]
; [uintegerR (:: (:+ digitR) (:* #\#))]
; [prefixR (:or (:: radixR exactness)
; (:: exactness radixR))]
[num2 (:: prefix2 complex2)]
[complex2 (:or real2
(:: real2 "@" real2)
(:: real2 "+" ureal2 "i")
(:: real2 "-" ureal2 "i")
(:: real2 "+i")
(:: real2 "-i")
(:: "+" ureal2 "i")
(:: "-" ureal2 "i")
(:: "+i")
(:: "-i"))]
[real2 (:: sign ureal2)]
[ureal2 (:or uinteger2 (:: uinteger2 "/" uinteger2))]
[uinteger2 (:: (:+ digit2) (:* #\#))]
[prefix2 (:or (:: radix2 exactness)
(:: exactness radix2))]
[radix2 "#b"]
[digit2 (:or "0" "1")]
[num8 (:: prefix8 complex8)]
[complex8 (:or real8
(:: real8 "@" real8)
(:: real8 "+" ureal8 "i")
(:: real8 "-" ureal8 "i")
(:: real8 "+i")
(:: real8 "-i")
(:: "+" ureal8 "i")
(:: "-" ureal8 "i")
[num2 (:: prefix2 complex2)]
[complex2 (:or real2
(:: real2 "@" real2)
(:: real2 "+" ureal2 "i")
(:: real2 "-" ureal2 "i")
(:: real2 "+i")
(:: real2 "-i")
(:: "+" ureal2 "i")
(:: "-" ureal2 "i")
(:: "+i")
(:: "-i"))]
[real2 (:: sign ureal2)]
[ureal2 (:or uinteger2 (:: uinteger2 "/" uinteger2))]
[uinteger2 (:: (:+ digit2) (:* #\#))]
[prefix2 (:or (:: radix2 exactness)
(:: exactness radix2))]
[radix2 "#b"]
[digit2 (:or "0" "1")]
[num8 (:: prefix8 complex8)]
[complex8 (:or real8
(:: real8 "@" real8)
(:: real8 "+" ureal8 "i")
(:: real8 "-" ureal8 "i")
(:: real8 "+i")
(:: real8 "-i")
(:: "+" ureal8 "i")
(:: "-" ureal8 "i")
(:: "+i")
(:: "-i"))]
[real8 (:: sign ureal8)]
[ureal8 (:or uinteger8 (:: uinteger8 "/" uinteger8))]
[uinteger8 (:: (:+ digit8) (:* #\#))]
[prefix8 (:or (:: radix8 exactness)
(:: exactness radix8))]
[radix8 "#o"]
[digit8 (:/ "0" "7")]
[num10 (:: prefix10 complex10)]
[complex10 (:or real10
(:: real10 "@" real10)
(:: real10 "+" ureal10 "i")
(:: real10 "-" ureal10 "i")
(:: real10 "+i")
(:: real10 "-i")
(:: "+" ureal10 "i")
(:: "-" ureal10 "i")
(:: "+i")
(:: "-i"))]
[real8 (:: sign ureal8)]
[ureal8 (:or uinteger8 (:: uinteger8 "/" uinteger8))]
[uinteger8 (:: (:+ digit8) (:* #\#))]
[prefix8 (:or (:: radix8 exactness)
(:: exactness radix8))]
[radix8 "#o"]
[digit8 (:/ "0" "7")]
[real10 (:: sign ureal10)]
[ureal10 (:or uinteger10 (:: uinteger10 "/" uinteger10) decimal10)]
[uinteger10 (:: (:+ digit10) (:* #\#))]
[prefix10 (:or (:: radix10 exactness)
(:: exactness radix10))]
[radix10 (:? "#d")]
[digit10 digit]
[decimal10 (:or (:: uinteger10 suffix)
(:: #\. (:+ digit10) (:* #\#) suffix)
(:: (:+ digit10) #\. (:* digit10) (:* #\#) suffix)
(:: (:+ digit10) (:+ #\#) #\. (:* #\#) suffix))]
[num10 (:: prefix10 complex10)]
[complex10 (:or real10
(:: real10 "@" real10)
(:: real10 "+" ureal10 "i")
(:: real10 "-" ureal10 "i")
(:: real10 "+i")
(:: real10 "-i")
(:: "+" ureal10 "i")
(:: "-" ureal10 "i")
(:: "+i")
(:: "-i"))]
[real10 (:: sign ureal10)]
[ureal10 (:or uinteger10 (:: uinteger10 "/" uinteger10) decimal10)]
[uinteger10 (:: (:+ digit10) (:* #\#))]
[prefix10 (:or (:: radix10 exactness)
(:: exactness radix10))]
[radix10 (:? "#d")]
[digit10 digit]
[decimal10 (:or (:: uinteger10 suffix)
(:: #\. (:+ digit10) (:* #\#) suffix)
(:: (:+ digit10) #\. (:* digit10) (:* #\#) suffix)
(:: (:+ digit10) (:+ #\#) #\. (:* #\#) suffix))]
[num16 (:: prefix16 complex16)]
[complex16 (:or real16
(:: real16 "@" real16)
(:: real16 "+" ureal16 "i")
(:: real16 "-" ureal16 "i")
(:: real16 "+i")
(:: real16 "-i")
(:: "+" ureal16 "i")
(:: "-" ureal16 "i")
"+i"
"-i")]
[real16 (:: sign ureal16)]
[ureal16 (:or uinteger16 (:: uinteger16 "/" uinteger16))]
[uinteger16 (:: (:+ digit16) (:* #\#))]
[prefix16 (:or (:: radix16 exactness)
(:: exactness radix16))]
[radix16 "#x"]
[digit16 (:or digit (:/ #\a #\f) (:/ #\A #\F))]
[num16 (:: prefix16 complex16)]
[complex16 (:or real16
(:: real16 "@" real16)
(:: real16 "+" ureal16 "i")
(:: real16 "-" ureal16 "i")
(:: real16 "+i")
(:: real16 "-i")
(:: "+" ureal16 "i")
(:: "-" ureal16 "i")
"+i"
"-i")]
[real16 (:: sign ureal16)]
[ureal16 (:or uinteger16 (:: uinteger16 "/" uinteger16))]
[uinteger16 (:: (:+ digit16) (:* #\#))]
[prefix16 (:or (:: radix16 exactness)
(:: exactness radix16))]
[radix16 "#x"]
[digit16 (:or digit (:/ #\a #\f) (:/ #\A #\F))]
[suffix (:or "" (:: exponent-marker sign (:+ digit10)))]
[exponent-marker (:or "e" "s" "f" "d" "l")]
[sign (:or "" "+" "-")]
[exactness (:or "" "#i" "#e")])
[suffix (:or "" (:: exponent-marker sign (:+ digit10)))]
[exponent-marker (:or "e" "s" "f" "d" "l")]
[sign (:or "" "+" "-")]
[exactness (:or "" "#i" "#e")])
(define stx-for-original-property (read-syntax #f (open-input-string "original")))
(define stx-for-original-property (read-syntax #f (open-input-string "original")))
;; A macro to build the syntax object
(define-syntax (build-so stx)
(syntax-case stx ()
((_ value start end)
(with-syntax ((start-pos (datum->syntax-object
(syntax end)
(string->symbol
(format "$~a-start-pos"
(syntax-object->datum (syntax start))))))
(end-pos (datum->syntax-object
(syntax end)
;; A macro to build the syntax object
(define-syntax (build-so stx)
(syntax-case stx ()
((_ value start end)
(with-syntax ((start-pos (datum->syntax
#'end
(string->symbol
(format "$~a-end-pos"
(syntax-object->datum (syntax end))))))
(source (datum->syntax-object
(syntax end)
'source-name)))
(syntax
(datum->syntax-object
#f
value
(list source
(position-line start-pos)
(position-col start-pos)
(position-offset start-pos)
(- (position-offset end-pos)
(position-offset start-pos)))
stx-for-original-property))))))
(format "$~a-start-pos"
(syntax->datum #'start)))))
(end-pos (datum->syntax
#'end
(string->symbol
(format "$~a-end-pos"
(syntax->datum #'end)))))
(source (datum->syntax
#'end
'source-name)))
(syntax
(datum->syntax
#f
value
(list source
(position-line start-pos)
(position-col start-pos)
(position-offset start-pos)
(- (position-offset end-pos)
(position-offset start-pos)))
stx-for-original-property))))))
(define (scheme-parser source-name)
(parser
(src-pos)
(define (scheme-parser source-name)
(parser
(src-pos)
(start s)
(end EOF)
(error (lambda (a name val start end)
(raise-read-error
"read-error"
source-name
(position-line start)
(position-col start)
(position-offset start)
(- (position-offset end)
(position-offset start)))))
(tokens data delim)
(start s)
(end EOF)
(error (lambda (a name val start end)
(raise-read-error
"read-error"
source-name
(position-line start)
(position-col start)
(position-offset start)
(- (position-offset end)
(position-offset start)))))
(tokens data delim)
(grammar
(grammar
(s [(sexp-list) (reverse $1)])
(s [(sexp-list) (reverse $1)])
(sexp [(DATUM) (build-so $1 1 1)]
[(OP sexp-list CP) (build-so (reverse $2) 1 3)]
[(HASHOP sexp-list CP) (build-so (list->vector (reverse $2)) 1 3)]
[(QUOTE sexp) (build-so (list 'quote $2) 1 2)]
[(QUASIQUOTE sexp) (build-so (list 'quasiquote $2) 1 2)]
[(UNQUOTE sexp) (build-so (list 'unquote $2) 1 2)]
[(UNQUOTE-SPLICING sexp) (build-so (list 'unquote-splicing $2) 1 2)]
[(OP sexp-list DOT sexp CP) (build-so (append (reverse $2) $4) 1 5)])
(sexp [(DATUM) (build-so $1 1 1)]
[(OP sexp-list CP) (build-so (reverse $2) 1 3)]
[(HASHOP sexp-list CP) (build-so (list->vector (reverse $2)) 1 3)]
[(QUOTE sexp) (build-so (list 'quote $2) 1 2)]
[(QUASIQUOTE sexp) (build-so (list 'quasiquote $2) 1 2)]
[(UNQUOTE sexp) (build-so (list 'unquote $2) 1 2)]
[(UNQUOTE-SPLICING sexp) (build-so (list 'unquote-splicing $2) 1 2)]
[(OP sexp-list DOT sexp CP) (build-so (append (reverse $2) $4) 1 5)])
(sexp-list [() null]
[(sexp-list sexp) (cons $2 $1)]))))
(define (rs sn ip)
(port-count-lines! ip)
((scheme-parser sn) (lambda () (scheme-lexer ip))))
(sexp-list [() null]
[(sexp-list sexp) (cons $2 $1)]))))
(define readsyntax
(case-lambda ((sn) (rs sn (current-input-port)))
((sn ip) (rs sn ip))))
(define (rs sn ip)
(port-count-lines! ip)
((scheme-parser sn) (lambda () (scheme-lexer ip))))
(provide (rename readsyntax read-syntax))
(define readsyntax
(case-lambda ((sn) (rs sn (current-input-port)))
((sn ip) (rs sn ip))))
)
(provide (rename-out [readsyntax read-syntax]))

@ -1,24 +1,23 @@
(module lex-plt-v200 mzscheme
(require br-parser-tools/lex
(prefix : br-parser-tools/lex-sre))
#lang racket/base
(require (for-syntax racket/base)
br-parser-tools/lex
(prefix-in : br-parser-tools/lex-sre))
(provide epsilon
~
(rename :* *)
(rename :+ +)
(rename :? ?)
(rename :or :)
(rename :& &)
(rename :: @)
(rename :~ ^)
(rename :/ -))
(provide epsilon ~
(rename-out [:* *]
[:+ +]
[:? ?]
[:or :]
[:& &]
[:: @]
[:~ ^]
[:/ -]))
(define-lex-trans epsilon
(syntax-rules ()
((_) "")))
(define-lex-trans ~
(syntax-rules ()
((_ re) (complement re)))))
(define-lex-trans (epsilon stx)
(syntax-case stx ()
[(_) #'""]))
(define-lex-trans (~ stx)
(syntax-case stx ()
[(_ RE) #'(complement RE)]))

@ -1,119 +1,103 @@
(module lex-sre mzscheme
(require br-parser-tools/lex)
#lang racket/base
(require (for-syntax racket/base)
br-parser-tools/lex)
(provide (rename sre-* *)
(rename sre-+ +)
?
(rename sre-= =)
(rename sre->= >=)
**
(rename sre-or or)
:
seq
&
~
(rename sre-- -)
(rename sre-/ /)
/-only-chars)
(provide (rename-out [sre-* *]
[sre-+ +]
[sre-= =]
[sre->= >=]
[sre-or or]
[sre-- -]
[sre-/ /])
? ** : seq & ~ /-only-chars)
(define-lex-trans sre-*
(syntax-rules ()
((_ re ...)
(repetition 0 +inf.0 (union re ...)))))
(define-lex-trans (sre-* stx)
(syntax-case stx ()
[(_ RE ...)
#'(repetition 0 +inf.0 (union RE ...))]))
(define-lex-trans sre-+
(syntax-rules ()
((_ re ...)
(repetition 1 +inf.0 (union re ...)))))
(define-lex-trans (sre-+ stx)
(syntax-case stx ()
[(_ RE ...)
#'(repetition 1 +inf.0 (union RE ...))]))
(define-lex-trans ?
(syntax-rules ()
((_ re ...)
(repetition 0 1 (union re ...)))))
(define-lex-trans (? stx)
(syntax-case stx ()
[(_ RE ...)
#'(repetition 0 1 (union RE ...))]))
(define-lex-trans sre-=
(syntax-rules ()
((_ n re ...)
(repetition n n (union re ...)))))
(define-lex-trans (sre-= stx)
(syntax-case stx ()
[(_ N RE ...)
#'(repetition N N (union RE ...))]))
(define-lex-trans sre->=
(syntax-rules ()
((_ n re ...)
(repetition n +inf.0 (union re ...)))))
(define-lex-trans (sre->= stx)
(syntax-case stx ()
[(_ N RE ...)
#'(repetition N +inf.0 (union RE ...))]))
(define-lex-trans **
(syntax-rules ()
((_ low #f re ...)
(** low +inf.0 re ...))
((_ low high re ...)
(repetition low high (union re ...)))))
(define-lex-trans (** stx)
(syntax-case stx ()
[(_ LOW #f RE ...)
#'(** LOW +inf.0 RE ...)]
[(_ LOW HIGH RE ...)
#'(repetition LOW HIGH (union RE ...))]))
(define-lex-trans sre-or
(syntax-rules ()
((_ re ...)
(union re ...))))
(define-lex-trans (sre-or stx)
(syntax-case stx ()
[(_ RE ...)
#'(union RE ...)]))
(define-lex-trans :
(syntax-rules ()
((_ re ...)
(concatenation re ...))))
(define-lex-trans (: stx)
(syntax-case stx ()
[(_ RE ...)
#'(concatenation RE ...)]))
(define-lex-trans seq
(syntax-rules ()
((_ re ...)
(concatenation re ...))))
(define-lex-trans (seq stx)
(syntax-case stx ()
[(_ RE ...)
#'(concatenation RE ...)]))
(define-lex-trans &
(syntax-rules ()
((_ re ...)
(intersection re ...))))
(define-lex-trans (& stx)
(syntax-case stx ()
[(_ RE ...)
#'(intersection RE ...)]))
(define-lex-trans ~
(syntax-rules ()
((_ re ...)
(char-complement (union re ...)))))
(define-lex-trans (~ stx)
(syntax-case stx ()
[(_ RE ...)
#'(char-complement (union RE ...))]))
;; set difference
(define-lex-trans (sre-- stx)
(syntax-case stx ()
((_)
(raise-syntax-error #f
"must have at least one argument"
stx))
((_ big-re re ...)
(syntax (& big-re (complement (union re ...)))))))
;; set difference
(define-lex-trans (sre-- stx)
(syntax-case stx ()
[(_)
(raise-syntax-error #f
"must have at least one argument"
stx)]
[(_ BIG-RE RE ...)
#'(& BIG-RE (complement (union RE ...)))]))
(define-lex-trans (sre-/ stx)
(syntax-case stx ()
((_ range ...)
(let ((chars
(apply append (map (lambda (r)
(let ((x (syntax-e r)))
(cond
((char? x) (list x))
((string? x) (string->list x))
(else
(raise-syntax-error
#f
"not a char or string"
stx
r)))))
(syntax->list (syntax (range ...)))))))
(unless (even? (length chars))
(raise-syntax-error
#f
"not given an even number of characters"
stx))
#`(/-only-chars #,@chars)))))
(define-lex-trans (sre-/ stx)
(syntax-case stx ()
[(_ RANGE ...)
(let ([chars
(apply append (for/list ([r (in-list (syntax->list #'(RANGE ...)))])
(let ([x (syntax-e r)])
(cond
[(char? x) (list x)]
[(string? x) (string->list x)]
[else
(raise-syntax-error #f "not a char or string" stx r)]))))])
(unless (even? (length chars))
(raise-syntax-error #f "not given an even number of characters" stx))
#`(/-only-chars #,@chars))]))
(define-lex-trans /-only-chars
(syntax-rules ()
((_ c1 c2)
(char-range c1 c2))
((_ c1 c2 c ...)
(union (char-range c1 c2)
(/-only-chars c ...)))))
(define-lex-trans (/-only-chars stx)
(syntax-case stx ()
[(_ C1 C2)
#'(char-range C1 C2)]
[(_ C1 C2 C ...)
#'(union (char-range C1 C2) (/-only-chars C ...))]))
)

@ -3,7 +3,7 @@
;; Provides the syntax used to create lexers and the functions needed to
;; create and use the buffer that the lexer reads from. See docs.
(require (for-syntax mzlib/list
(require (for-syntax racket/list
syntax/stx
syntax/define
syntax/boundmap
@ -14,7 +14,7 @@
racket/base
racket/promise))
(require mzlib/stxparam
(require racket/stxparam
syntax/readerr
"private-lex/token.rkt")
@ -30,7 +30,7 @@
file-path
lexer-file-path ;; alternate name
;; Lex abbrevs for unicode char sets. See mzscheme manual section 3.4.
;; Lex abbrevs for unicode char sets.
any-char any-string nothing alphabetic lower-case upper-case title-case
numeric symbolic punctuation graphic whitespace blank iso-control
@ -77,9 +77,9 @@
(let ()
(define spec/re-acts (syntax->list #'RE+ACTS))
(for/and ([x (in-list spec/re-acts)])
(syntax-case x ()
[(RE ACT) #t]
[else (raise-syntax-error caller "not a regular expression / action pair" stx x)]))
(syntax-case x ()
[(RE ACT) #t]
[else (raise-syntax-error caller "not a regular expression / action pair" stx x)]))
(define eof-act (get-special-action spec/re-acts #'eof (case src-loc-style
[(lexer-src-pos) #'(return-without-pos eof)]
[(lexer-srcloc) #'(return-without-srcloc eof)]
@ -212,92 +212,90 @@
(define (get-next-state char table)
(and table (get-next-state-helper char 0 (vector-length table) table)))
(define (lexer-body start-state trans-table actions no-lookahead special-action
has-special-comment-action? special-comment-action eof-action)
(letrec ([lexer
(λ (ip)
(let ((first-pos (get-position ip))
(first-char (peek-char-or-special ip 0)))
;(printf "(peek-char-or-special port 0) = ~e\n" first-char)
(cond
[(eof-object? first-char)
(do-match ip first-pos eof-action (read-char-or-special ip))]
[(special-comment? first-char)
(read-char-or-special ip)
(cond
(has-special-comment-action?
(do-match ip first-pos special-comment-action #f))
(else (lexer ip)))]
[(not (char? first-char))
(do-match ip first-pos special-action (read-char-or-special ip))]
[else
(let lexer-loop (
;; current-state
(state start-state)
;; the character to transition on
(char first-char)
;; action for the longest match seen thus far
;; including a match at the current state
(longest-match-action
(vector-ref actions start-state))
;; how many bytes precede char
(length-bytes 0)
;; how many characters have been read
;; including the one just read
(length-chars 1)
;; how many characters are in the longest match
(longest-match-length 0))
(let ([next-state
(cond
[(not (char? char)) #f]
[else (get-next-state (char->integer char)
(vector-ref trans-table state))])])
(cond
[(not next-state)
(check-match ip first-pos longest-match-length
length-chars longest-match-action)]
[(vector-ref no-lookahead next-state)
(let ((act (vector-ref actions next-state)))
(check-match ip
first-pos
(if act length-chars longest-match-length)
length-chars
(if act act longest-match-action)))]
[else
(let* ([act (vector-ref actions next-state)]
[next-length-bytes (+ (char-utf-8-length char) length-bytes)]
[next-char (peek-char-or-special ip next-length-bytes)])
#;(printf "(peek-char-or-special port ~e) = ~e\n"
next-length-bytes next-char)
(lexer-loop next-state
next-char
(if act
act
longest-match-action)
next-length-bytes
(add1 length-chars)
(if act
length-chars
longest-match-length)))])))])))])
(λ (ip)
(unless (input-port? ip)
(raise-argument-error 'lexer "input-port?" 0 ip))
(lexer ip))))
(define ((lexer-body start-state trans-table actions no-lookahead special-action
has-special-comment-action? special-comment-action eof-action) ip)
(define (lexer ip)
(define first-pos (get-position ip))
(define first-char (peek-char-or-special ip 0))
;(printf "(peek-char-or-special port 0) = ~e\n" first-char)
(cond
[(eof-object? first-char)
(do-match ip first-pos eof-action (read-char-or-special ip))]
[(special-comment? first-char)
(read-char-or-special ip)
(cond
(has-special-comment-action?
(do-match ip first-pos special-comment-action #f))
(else (lexer ip)))]
[(not (char? first-char))
(do-match ip first-pos special-action (read-char-or-special ip))]
[else
(let lexer-loop (
;; current-state
[state start-state]
;; the character to transition on
[char first-char]
;; action for the longest match seen thus far
;; including a match at the current state
[longest-match-action
(vector-ref actions start-state)]
;; how many bytes precede char
[length-bytes 0]
;; how many characters have been read
;; including the one just read
[length-chars 1]
;; how many characters are in the longest match
[longest-match-length 0])
(define next-state
(cond
[(not (char? char)) #f]
[else (get-next-state (char->integer char)
(vector-ref trans-table state))]))
(cond
[(not next-state)
(check-match ip first-pos longest-match-length
length-chars longest-match-action)]
[(vector-ref no-lookahead next-state)
(define act (vector-ref actions next-state))
(check-match ip
first-pos
(if act length-chars longest-match-length)
length-chars
(if act act longest-match-action))]
[else
(define act (vector-ref actions next-state))
(define next-length-bytes (+ (char-utf-8-length char) length-bytes))
(define next-char (peek-char-or-special ip next-length-bytes))
#;(printf "(peek-char-or-special port ~e) = ~e\n"
next-length-bytes next-char)
(lexer-loop next-state
next-char
(if act
act
longest-match-action)
next-length-bytes
(add1 length-chars)
(if act
length-chars
longest-match-length))]))]))
(unless (input-port? ip)
(raise-argument-error 'lexer "input-port?" 0 ip))
(lexer ip))
(define (check-match lb first-pos longest-match-length length longest-match-action)
(unless longest-match-action
(let* ([match (read-string length lb)]
[end-pos (get-position lb)])
(raise-read-error
(format "lexer: No match found in input starting with: ~a" match)
(file-path)
(position-line first-pos)
(position-col first-pos)
(position-offset first-pos)
(- (position-offset end-pos) (position-offset first-pos)))))
(let ([match (read-string longest-match-length lb)])
;(printf "(read-string ~e port) = ~e\n" longest-match-length match)
(do-match lb first-pos longest-match-action match)))
(define match (read-string length lb))
(define end-pos (get-position lb))
(raise-read-error
(format "lexer: No match found in input starting with: ~a" match)
(file-path)
(position-line first-pos)
(position-col first-pos)
(position-offset first-pos)
(- (position-offset end-pos) (position-offset first-pos))))
(define match (read-string longest-match-length lb))
;(printf "(read-string ~e port) = ~e\n" longest-match-length match)
(do-match lb first-pos longest-match-action match))
(define file-path (make-parameter #f))
(define lexer-file-path file-path)
@ -325,10 +323,10 @@
(force whitespace-ranges)
(force blank-ranges)
(force iso-control-ranges)))])
`(union ,@(map (λ (x)
`(char-range ,(integer->char (car x))
,(integer->char (cdr x))))
range)))]
`(union ,@(map (λ (x)
`(char-range ,(integer->char (car x))
,(integer->char (cdr x))))
range)))]
[(NAMES ...) (for/list ([sym (in-list '(alphabetic
lower-case
upper-case
@ -340,7 +338,7 @@
whitespace
blank
iso-control))])
(datum->syntax #'CTXT sym #f))])
(datum->syntax #'CTXT sym #f))])
#'(define-lex-abbrevs (NAMES RANGES) ...))]))
(define-lex-abbrev any-char (char-complement (union)))

@ -1,5 +1,4 @@
#lang racket/base
(provide (all-defined-out))
(require syntax/stx)
@ -7,10 +6,10 @@
;; Returns the first action from a rule of the form ((which-special) action)
(define (get-special-action rules which-special none)
(cond
((null? rules) none)
(else
[(null? rules) none]
[else
(syntax-case (car rules) ()
[((special) ACT)
(and (identifier? #'special) (module-or-top-identifier=? (syntax special) which-special))
(and (identifier? #'special) (module-or-top-identifier=? #'special which-special))
#'ACT]
[_ (get-special-action (cdr rules) which-special none)]))))
[_ (get-special-action (cdr rules) which-special none)])]))

@ -1,303 +1,297 @@
(module deriv mzscheme
(require mzlib/list
(prefix is: mzlib/integer-set)
"re.rkt"
"util.rkt")
#lang racket/base
(require racket/list
(prefix-in is: data/integer-set)
"re.rkt"
"util.rkt")
(provide build-dfa print-dfa (struct dfa (num-states start-state final-states/actions transitions)))
(provide build-dfa print-dfa (struct-out dfa))
(define e (build-epsilon))
(define z (build-zero))
(define e (build-epsilon))
(define z (build-zero))
;; Don't do anything with this one but extract the chars
(define all-chars (->re `(char-complement (union)) (make-cache)))
;; Don't do anything with this one but extract the chars
(define all-chars (->re `(char-complement (union)) (make-cache)))
;; get-char-groups : re bool -> (list-of char-setR?)
;; Collects the char-setRs in r that could be used in
;; taking the derivative of r.
(define (get-char-groups r found-negation)
(cond
((or (eq? r e) (eq? r z)) null)
((char-setR? r) (list r))
((concatR? r)
(if (re-nullable? (concatR-re1 r))
(append (get-char-groups (concatR-re1 r) found-negation)
(get-char-groups (concatR-re2 r) found-negation))
(get-char-groups (concatR-re1 r) found-negation)))
((repeatR? r)
(get-char-groups (repeatR-re r) found-negation))
((orR? r)
(apply append (map (lambda (x) (get-char-groups x found-negation)) (orR-res r))))
((andR? r)
(apply append (map (lambda (x) (get-char-groups x found-negation)) (andR-res r))))
((negR? r)
(if found-negation
(get-char-groups (negR-re r) #t)
(cons all-chars (get-char-groups (negR-re r) #t))))))
;; get-char-groups : re bool -> (list-of char-setR?)
;; Collects the char-setRs in r that could be used in
;; taking the derivative of r.
(define (get-char-groups r found-negation)
(cond
[(or (eq? r e) (eq? r z)) null]
[(char-setR? r) (list r)]
[(concatR? r)
(if (re-nullable? (concatR-re1 r))
(append (get-char-groups (concatR-re1 r) found-negation)
(get-char-groups (concatR-re2 r) found-negation))
(get-char-groups (concatR-re1 r) found-negation))]
[(repeatR? r)
(get-char-groups (repeatR-re r) found-negation)]
[(orR? r)
(apply append (map (λ (x) (get-char-groups x found-negation)) (orR-res r)))]
[(andR? r)
(apply append (map (λ (x) (get-char-groups x found-negation)) (andR-res r)))]
[(negR? r)
(if found-negation
(get-char-groups (negR-re r) #t)
(cons all-chars (get-char-groups (negR-re r) #t)))]))
(test-block ((c (make-cache))
(r1 (->re #\1 c))
(r2 (->re #\2 c)))
((get-char-groups e #f) null)
((get-char-groups z #f) null)
((get-char-groups r1 #f) (list r1))
((get-char-groups (->re `(concatenation ,r1 ,r2) c) #f)
(list r1))
((get-char-groups (->re `(concatenation ,e ,r2) c) #f)
(list r2))
((get-char-groups (->re `(concatenation (repetition 0 +inf.0 ,r1) ,r2) c) #f)
(list r1 r2))
((get-char-groups (->re `(repetition 0 +inf.0 ,r1) c) #f)
(list r1))
((get-char-groups
(->re `(union (repetition 0 +inf.0 ,r1)
(concatenation (repetition 0 +inf.0 ,r2) "3") "4") c) #f)
(list r1 r2 (->re "3" c) (->re "4" c)))
((get-char-groups (->re `(complement ,r1) c) #f)
(list all-chars r1))
((get-char-groups
(->re `(intersection (repetition 0 +inf.0 ,r1)
(concatenation (repetition 0 +inf.0 ,r2) "3") "4") c) #f)
(list r1 r2 (->re "3" c) (->re "4" c)))
)
(define loc:member? is:member?)
(test-block ((c (make-cache))
(r1 (->re #\1 c))
(r2 (->re #\2 c)))
((get-char-groups e #f) null)
((get-char-groups z #f) null)
((get-char-groups r1 #f) (list r1))
((get-char-groups (->re `(concatenation ,r1 ,r2) c) #f)
(list r1))
((get-char-groups (->re `(concatenation ,e ,r2) c) #f)
(list r2))
((get-char-groups (->re `(concatenation (repetition 0 +inf.0 ,r1) ,r2) c) #f)
(list r1 r2))
((get-char-groups (->re `(repetition 0 +inf.0 ,r1) c) #f)
(list r1))
((get-char-groups
(->re `(union (repetition 0 +inf.0 ,r1)
(concatenation (repetition 0 +inf.0 ,r2) "3") "4") c) #f)
(list r1 r2 (->re "3" c) (->re "4" c)))
((get-char-groups (->re `(complement ,r1) c) #f)
(list all-chars r1))
((get-char-groups
(->re `(intersection (repetition 0 +inf.0 ,r1)
(concatenation (repetition 0 +inf.0 ,r2) "3") "4") c) #f)
(list r1 r2 (->re "3" c) (->re "4" c)))
)
(define loc:member? is:member?)
;; deriveR : re char cache -> re
(define (deriveR r c cache)
(cond
((or (eq? r e) (eq? r z)) z)
((char-setR? r)
(if (loc:member? c (char-setR-chars r)) e z))
((concatR? r)
(let* ((r1 (concatR-re1 r))
(r2 (concatR-re2 r))
(d (build-concat (deriveR r1 c cache) r2 cache)))
(if (re-nullable? r1)
(build-or (list d (deriveR r2 c cache)) cache)
d)))
((repeatR? r)
(build-concat (deriveR (repeatR-re r) c cache)
(build-repeat (sub1 (repeatR-low r))
(sub1 (repeatR-high r))
(repeatR-re r) cache)
cache))
((orR? r)
(build-or (map (lambda (x) (deriveR x c cache))
(orR-res r))
cache))
((andR? r)
(build-and (map (lambda (x) (deriveR x c cache))
(andR-res r))
cache))
((negR? r)
(build-neg (deriveR (negR-re r) c cache) cache))))
;; deriveR : re char cache -> re
(define (deriveR r c cache)
(cond
[(or (eq? r e) (eq? r z)) z]
[(char-setR? r)
(if (loc:member? c (char-setR-chars r)) e z)]
[(concatR? r)
(define r1 (concatR-re1 r))
(define r2 (concatR-re2 r))
(define d (build-concat (deriveR r1 c cache) r2 cache))
(if (re-nullable? r1)
(build-or (list d (deriveR r2 c cache)) cache)
d)]
[(repeatR? r)
(build-concat (deriveR (repeatR-re r) c cache)
(build-repeat (sub1 (repeatR-low r))
(sub1 (repeatR-high r))
(repeatR-re r) cache)
cache)]
[(orR? r)
(build-or (map (λ (x) (deriveR x c cache))
(orR-res r))
cache)]
[(andR? r)
(build-and (map (λ (x) (deriveR x c cache))
(andR-res r))
cache)]
[(negR? r)
(build-neg (deriveR (negR-re r) c cache) cache)]))
(test-block ((c (make-cache))
(a (char->integer #\a))
(b (char->integer #\b))
(r1 (->re #\a c))
(r2 (->re `(repetition 0 +inf.0 #\a) c))
(r3 (->re `(repetition 0 +inf.0 ,r2) c))
(r4 (->re `(concatenation #\a ,r2) c))
(r5 (->re `(repetition 0 +inf.0 ,r4) c))
(r6 (->re `(union ,r5 #\a) c))
(r7 (->re `(concatenation ,r2 ,r2) c))
(r8 (->re `(complement ,r4) c))
(r9 (->re `(intersection ,r2 ,r4) c)))
((deriveR e a c) z)
((deriveR z a c) z)
((deriveR r1 b c) z)
((deriveR r1 a c) e)
((deriveR r2 a c) r2)
((deriveR r2 b c) z)
((deriveR r3 a c) r2)
((deriveR r3 b c) z)
((deriveR r4 a c) r2)
((deriveR r4 b c) z)
((deriveR r5 a c) (->re `(concatenation ,r2 ,r5) c))
((deriveR r5 b c) z)
((deriveR r6 a c) (->re `(union (concatenation ,r2 ,r5) "") c))
((deriveR r6 b c) z)
((deriveR r7 a c) (->re `(union (concatenation ,r2 ,r2) ,r2) c))
((deriveR r7 b c) z)
((deriveR r8 a c) (->re `(complement, r2) c))
((deriveR r8 b c) (->re `(complement ,z) c))
((deriveR r9 a c) r2)
((deriveR r9 b c) z)
((deriveR (->re `(repetition 1 2 "ab") c) a c)
(->re `(concatenation "b" (repetition 0 1 "ab")) c)))
(test-block ((c (make-cache))
(a (char->integer #\a))
(b (char->integer #\b))
(r1 (->re #\a c))
(r2 (->re `(repetition 0 +inf.0 #\a) c))
(r3 (->re `(repetition 0 +inf.0 ,r2) c))
(r4 (->re `(concatenation #\a ,r2) c))
(r5 (->re `(repetition 0 +inf.0 ,r4) c))
(r6 (->re `(union ,r5 #\a) c))
(r7 (->re `(concatenation ,r2 ,r2) c))
(r8 (->re `(complement ,r4) c))
(r9 (->re `(intersection ,r2 ,r4) c)))
((deriveR e a c) z)
((deriveR z a c) z)
((deriveR r1 b c) z)
((deriveR r1 a c) e)
((deriveR r2 a c) r2)
((deriveR r2 b c) z)
((deriveR r3 a c) r2)
((deriveR r3 b c) z)
((deriveR r4 a c) r2)
((deriveR r4 b c) z)
((deriveR r5 a c) (->re `(concatenation ,r2 ,r5) c))
((deriveR r5 b c) z)
((deriveR r6 a c) (->re `(union (concatenation ,r2 ,r5) "") c))
((deriveR r6 b c) z)
((deriveR r7 a c) (->re `(union (concatenation ,r2 ,r2) ,r2) c))
((deriveR r7 b c) z)
((deriveR r8 a c) (->re `(complement, r2) c))
((deriveR r8 b c) (->re `(complement ,z) c))
((deriveR r9 a c) r2)
((deriveR r9 b c) z)
((deriveR (->re `(repetition 1 2 "ab") c) a c)
(->re `(concatenation "b" (repetition 0 1 "ab")) c)))
;; An re-action is (cons re action)
;; An re-action is (cons re action)
;; derive : (list-of re-action) char cache -> (union (list-of re-action) #f)
;; applies deriveR to all the re-actions's re parts.
;; Returns #f if the derived state is equivalent to z.
(define (derive r c cache)
(let ((new-r (map (lambda (ra)
(cons (deriveR (car ra) c cache) (cdr ra)))
r)))
(if (andmap (lambda (x) (eq? z (car x)))
new-r)
#f
new-r)))
;; derive : (list-of re-action) char cache -> (union (list-of re-action) #f)
;; applies deriveR to all the re-actions's re parts.
;; Returns #f if the derived state is equivalent to z.
(define (derive r c cache)
(define new-r (for/list ([ra (in-list r)])
(cons (deriveR (car ra) c cache) (cdr ra))))
(if (andmap (λ (x) (eq? z (car x))) new-r)
#f
new-r))
(test-block ((c (make-cache))
(r1 (->re #\1 c))
(r2 (->re #\2 c)))
((derive null (char->integer #\1) c) #f)
((derive (list (cons r1 1) (cons r2 2)) (char->integer #\1) c)
(list (cons e 1) (cons z 2)))
((derive (list (cons r1 1) (cons r2 2)) (char->integer #\3) c) #f))
(test-block ((c (make-cache))
(r1 (->re #\1 c))
(r2 (->re #\2 c)))
((derive null (char->integer #\1) c) #f)
((derive (list (cons r1 1) (cons r2 2)) (char->integer #\1) c)
(list (cons e 1) (cons z 2)))
((derive (list (cons r1 1) (cons r2 2)) (char->integer #\3) c) #f))
;; get-final : (list-of re-action) -> (union #f syntax-object)
;; An re that accepts e represents a final state. Return the
;; action from the first final state or #f if there is none.
(define (get-final res)
(cond
((null? res) #f)
((re-nullable? (caar res)) (cdar res))
(else (get-final (cdr res)))))
;; get-final : (list-of re-action) -> (union #f syntax-object)
;; An re that accepts e represents a final state. Return the
;; action from the first final state or #f if there is none.
(define (get-final res)
(cond
[(null? res) #f]
[(re-nullable? (caar res)) (cdar res)]
[else (get-final (cdr res))]))
(test-block ((c->i char->integer)
(c (make-cache))
(r1 (->re #\a c))
(r2 (->re #\b c))
(b (list (cons z 1) (cons z 2) (cons z 3) (cons e 4) (cons z 5)))
(a (list (cons r1 1) (cons r2 2))))
((derive null (c->i #\a) c) #f)
((derive a (c->i #\a) c) (list (cons e 1) (cons z 2)))
((derive a (c->i #\b) c) (list (cons z 1) (cons e 2)))
((derive a (c->i #\c) c) #f)
((derive (list (cons (->re `(union " " "\n" ",") c) 1)
(cons (->re `(concatenation (repetition 0 1 "-")
(repetition 1 +inf.0 (char-range "0" "9"))) c) 2)
(cons (->re `(concatenation "-" (repetition 1 +inf.0 "-")) c) 3)
(cons (->re "[" c) 4)
(cons (->re "]" c) 5)) (c->i #\[) c)
b)
((get-final a) #f)
((get-final (list (cons e 1) (cons e 2))) 1)
((get-final b) 4))
(test-block ((c->i char->integer)
(c (make-cache))
(r1 (->re #\a c))
(r2 (->re #\b c))
(b (list (cons z 1) (cons z 2) (cons z 3) (cons e 4) (cons z 5)))
(a (list (cons r1 1) (cons r2 2))))
((derive null (c->i #\a) c) #f)
((derive a (c->i #\a) c) (list (cons e 1) (cons z 2)))
((derive a (c->i #\b) c) (list (cons z 1) (cons e 2)))
((derive a (c->i #\c) c) #f)
((derive (list (cons (->re `(union " " "\n" ",") c) 1)
(cons (->re `(concatenation (repetition 0 1 "-")
(repetition 1 +inf.0 (char-range "0" "9"))) c) 2)
(cons (->re `(concatenation "-" (repetition 1 +inf.0 "-")) c) 3)
(cons (->re "[" c) 4)
(cons (->re "]" c) 5)) (c->i #\[) c)
b)
((get-final a) #f)
((get-final (list (cons e 1) (cons e 2))) 1)
((get-final b) 4))
;; A state is (make-state (list-of re-action) nat)
(define-struct state (spec index))
;; A state is (make-state (list-of re-action) nat)
(define-struct state (spec index))
;; get->key : re-action -> (list-of nat)
;; states are indexed by the list of indexes of their res
(define (get-key s)
(map (lambda (x) (re-index (car x))) s))
;; get->key : re-action -> (list-of nat)
;; states are indexed by the list of indexes of their res
(define (get-key s)
(map (λ (x) (re-index (car x))) s))
(define loc:partition is:partition)
(define loc:partition is:partition)
;; compute-chars : (list-of state) -> (list-of char-set)
;; Computed the sets of equivalent characters for taking the
;; derivative of the car of st. Only one derivative per set need to be taken.
(define (compute-chars st)
(cond
((null? st) null)
(else
(loc:partition (map char-setR-chars
(apply append (map (lambda (x) (get-char-groups (car x) #f))
(state-spec (car st)))))))))
;; compute-chars : (list-of state) -> (list-of char-set)
;; Computed the sets of equivalent characters for taking the
;; derivative of the car of st. Only one derivative per set need to be taken.
(define (compute-chars st)
(cond
[(null? st) null]
[else
(loc:partition (map char-setR-chars
(apply append (map (λ (x) (get-char-groups (car x) #f))
(state-spec (car st))))))]))
(test-block ((c (make-cache))
(c->i char->integer)
(r1 (->re `(char-range #\1 #\4) c))
(r2 (->re `(char-range #\2 #\3) c)))
((compute-chars null) null)
((compute-chars (list (make-state null 1))) null)
((map is:integer-set-contents
(compute-chars (list (make-state (list (cons r1 1) (cons r2 2)) 2))))
(list (is:integer-set-contents (is:make-range (c->i #\2) (c->i #\3)))
(is:integer-set-contents (is:union (is:make-range (c->i #\1))
(is:make-range (c->i #\4)))))))
(test-block ((c (make-cache))
(c->i char->integer)
(r1 (->re `(char-range #\1 #\4) c))
(r2 (->re `(char-range #\2 #\3) c)))
((compute-chars null) null)
((compute-chars (list (make-state null 1))) null)
((map is:integer-set-contents
(compute-chars (list (make-state (list (cons r1 1) (cons r2 2)) 2))))
(list (is:integer-set-contents (is:make-range (c->i #\2) (c->i #\3)))
(is:integer-set-contents (is:union (is:make-range (c->i #\1))
(is:make-range (c->i #\4)))))))
;; A dfa is (make-dfa int int
;; (list-of (cons int syntax-object))
;; (list-of (cons int (list-of (cons char-set int)))))
;; Each transitions is a state and a list of chars with the state to transition to.
;; The finals and transitions are sorted by state number, and duplicate free.
(define-struct dfa (num-states start-state final-states/actions transitions) (make-inspector))
;; A dfa is (make-dfa int int
;; (list-of (cons int syntax-object))
;; (list-of (cons int (list-of (cons char-set int)))))
;; Each transitions is a state and a list of chars with the state to transition to.
;; The finals and transitions are sorted by state number, and duplicate free.
(define-struct dfa (num-states start-state final-states/actions transitions) #:inspector (make-inspector))
(define loc:get-integer is:get-integer)
(define loc:get-integer is:get-integer)
;; build-dfa : (list-of re-action) cache -> dfa
(define (build-dfa rs cache)
(let* ((transitions (make-hash-table))
(get-state-number (make-counter))
(start (make-state rs (get-state-number))))
(cache (cons 'state (get-key rs)) (lambda () start))
(let loop ((old-states (list start))
(new-states null)
(all-states (list start))
(cs (compute-chars (list start))))
(cond
((and (null? old-states) (null? new-states))
(make-dfa (get-state-number) (state-index start)
(sort (filter (lambda (x) (cdr x))
(map (lambda (state)
(cons (state-index state) (get-final (state-spec state))))
all-states))
(lambda (a b) (< (car a) (car b))))
(sort (hash-table-map transitions
(lambda (state trans)
(cons (state-index state)
(map (lambda (t)
(cons (car t)
(state-index (cdr t))))
trans))))
(lambda (a b) (< (car a) (car b))))))
((null? old-states)
(loop new-states null all-states (compute-chars new-states)))
((null? cs)
(loop (cdr old-states) new-states all-states (compute-chars (cdr old-states))))
(else
(let* ((state (car old-states))
(c (car cs))
(new-re (derive (state-spec state) (loc:get-integer c) cache)))
(cond
(new-re
(let* ((new-state? #f)
(new-state (cache (cons 'state (get-key new-re))
(lambda ()
(set! new-state? #t)
(make-state new-re (get-state-number)))))
(new-all-states (if new-state? (cons new-state all-states) all-states)))
(hash-table-put! transitions
state
(cons (cons c new-state)
(hash-table-get transitions state
(lambda () null))))
(cond
(new-state?
(loop old-states (cons new-state new-states) new-all-states (cdr cs)))
(else
(loop old-states new-states new-all-states (cdr cs))))))
(else (loop old-states new-states all-states (cdr cs))))))))))
;; build-dfa : (list-of re-action) cache -> dfa
(define (build-dfa rs cache)
(let* ([transitions (make-hash)]
[get-state-number (make-counter)]
[start (make-state rs (get-state-number))])
(cache (cons 'state (get-key rs)) (λ () start))
(let loop ([old-states (list start)]
[new-states null]
[all-states (list start)]
[cs (compute-chars (list start))])
(cond
[(and (null? old-states) (null? new-states))
(make-dfa (get-state-number) (state-index start)
(sort (for*/list ([state (in-list all-states)]
[val (in-value (cons (state-index state) (get-final (state-spec state))))]
#:when (cdr val))
val)
< #:key car)
(sort (hash-map transitions
(λ (state trans)
(cons (state-index state)
(for/list ([t (in-list trans)])
(cons (car t)
(state-index (cdr t)))))))
< #:key car))]
[(null? old-states)
(loop new-states null all-states (compute-chars new-states))]
[(null? cs)
(loop (cdr old-states) new-states all-states (compute-chars (cdr old-states)))]
[else
(define state (car old-states))
(define c (car cs))
(define new-re (derive (state-spec state) (loc:get-integer c) cache))
(cond
[new-re
(let* ([new-state? #f]
[new-state (cache (cons 'state (get-key new-re))
(λ ()
(set! new-state? #t)
(make-state new-re (get-state-number))))]
[new-all-states (if new-state? (cons new-state all-states) all-states)])
(hash-set! transitions
state
(cons (cons c new-state)
(hash-ref transitions state
(λ () null))))
(cond
[new-state?
(loop old-states (cons new-state new-states) new-all-states (cdr cs))]
[else
(loop old-states new-states new-all-states (cdr cs))]))]
[else (loop old-states new-states all-states (cdr cs))])]))))
(define (print-dfa x)
(printf "number of states: ~a\n" (dfa-num-states x))
(printf "start state: ~a\n" (dfa-start-state x))
(printf "final states: ~a\n" (map car (dfa-final-states/actions x)))
(for-each (lambda (trans)
(printf "state: ~a\n" (car trans))
(for-each (lambda (rule)
(printf " -~a-> ~a\n"
(is:integer-set-contents (car rule))
(cdr rule)))
(cdr trans)))
(dfa-transitions x)))
(define (print-dfa x)
(printf "number of states: ~a\n" (dfa-num-states x))
(printf "start state: ~a\n" (dfa-start-state x))
(printf "final states: ~a\n" (map car (dfa-final-states/actions x)))
(for-each (λ (trans)
(printf "state: ~a\n" (car trans))
(for-each (λ (rule)
(printf " -~a-> ~a\n"
(is:integer-set-contents (car rule))
(cdr rule)))
(cdr trans)))
(dfa-transitions x)))
(define (build-test-dfa rs)
(let ((c (make-cache)))
(build-dfa (map (lambda (x) (cons (->re x c) 'action))
rs)
c)))
(define (build-test-dfa rs)
(define c (make-cache))
(build-dfa (map (λ (x) (cons (->re x c) 'action)) rs) c))
#|
@ -316,8 +310,8 @@
(build-test-dfa `((concatenation (repetition 0 +inf.0 (union #\a #\b)) #\a (union #\a #\b)
(union #\a #\b) (union #\a #\b) (union #\a #\b)))))
(define t9 (build-test-dfa `((concatenation "/*"
(complement (concatenation (intersection) "*/" (intersection)))
"*/"))))
(complement (concatenation (intersection) "*/" (intersection)))
"*/"))))
(define t11 (build-test-dfa `((complement "1"))))
(define t12 (build-test-dfa `((concatenation (intersection (concatenation (repetition 0 +inf.0 "a") "b")
(concatenation "a" (repetition 0 +inf.0 "b")))
@ -329,11 +323,11 @@
"]")))
(define y (build-test-dfa
`((repetition 1 +inf.0
(union (concatenation "|" (repetition 0 +inf.0 (char-complement "|")) "|")
(concatenation "|" (repetition 0 +inf.0 (char-complement "|"))))))))
(union (concatenation "|" (repetition 0 +inf.0 (char-complement "|")) "|")
(concatenation "|" (repetition 0 +inf.0 (char-complement "|"))))))))
(define t13 (build-test-dfa `((intersection (concatenation (intersection) "111" (intersection))
(complement (union (concatenation (intersection) "01")
(repetition 1 +inf.0 "1")))))))
(define t14 (build-test-dfa `((complement "1"))))
|#
)
(repetition 1 +inf.0 "1")))))))
(define t14 (build-test-dfa `((complement "1")))))
|#

@ -1,5 +1,5 @@
#lang scheme/base
(require (for-syntax scheme/base)
#lang racket/base
(require (for-syntax racket/base)
"../lex.rkt"
rackunit)

@ -1,179 +1,161 @@
(module front mzscheme
(require (prefix is: mzlib/integer-set)
mzlib/list
syntax/stx
"util.rkt"
"stx.rkt"
"re.rkt"
"deriv.rkt")
#lang racket/base
(require racket/base
racket/match
(prefix-in is: data/integer-set)
racket/list
syntax/stx
"util.rkt"
"stx.rkt"
"re.rkt"
"deriv.rkt")
(provide build-lexer)
(provide build-lexer)
(define-syntax time-label
(syntax-rules ()
((_ l e ...)
(begin
(printf "~a: " l)
(time (begin e ...))))))
(define-syntax time-label
(syntax-rules ()
((_ l e ...)
(begin
(printf "~a: " l)
(time (begin e ...))))))
;; A table is either
;; - (vector-of (union #f nat))
;; - (vector-of (vector-of (vector nat nat nat)))
;; A table is either
;; - (vector-of (union #f nat))
;; - (vector-of (vector-of (vector nat nat nat)))
(define loc:integer-set-contents is:integer-set-contents)
(define loc:integer-set-contents is:integer-set-contents)
;; dfa->1d-table : dfa -> (same as build-lexer)
(define (dfa->1d-table dfa)
(let ((state-table (make-vector (dfa-num-states dfa) #f))
(transition-cache (make-hash-table 'equal)))
(for-each
(lambda (trans)
(let* ((from-state (car trans))
(all-chars/to (cdr trans))
(flat-all-chars/to
(sort
(apply append
(map (lambda (chars/to)
(let ((char-ranges (loc:integer-set-contents (car chars/to)))
(to (cdr chars/to)))
(map (lambda (char-range)
(let ((entry (vector (car char-range) (cdr char-range) to)))
(hash-table-get transition-cache entry
(lambda ()
(hash-table-put! transition-cache
entry
entry)
entry))))
char-ranges)))
all-chars/to))
(lambda (a b)
(< (vector-ref a 0) (vector-ref b 0))))))
(vector-set! state-table from-state (list->vector flat-all-chars/to))))
(dfa-transitions dfa))
state-table))
;; dfa->1d-table : dfa -> (same as build-lexer)
(define (dfa->1d-table dfa)
(define state-table (make-vector (dfa-num-states dfa) #f))
(define transition-cache (make-hasheq))
(for ([trans (in-list (dfa-transitions dfa))])
(match-define (cons from-state all-chars/to) trans)
(define flat-all-chars/to
(sort
(for*/list ([chars/to (in-list all-chars/to)]
[char-ranges (in-value (loc:integer-set-contents (car chars/to)))]
[to (in-value (cdr chars/to))]
[char-range (in-list char-ranges)])
(define entry (vector (car char-range) (cdr char-range) to))
(hash-ref transition-cache entry (λ ()
(hash-set! transition-cache
entry
entry)
entry)))
< #:key (λ (v) (vector-ref v 0))))
(vector-set! state-table from-state (list->vector flat-all-chars/to)))
state-table)
(define loc:foldr is:foldr)
(define loc:foldr is:foldr)
;; dfa->2d-table : dfa -> (same as build-lexer)
(define (dfa->2d-table dfa)
(let (
;; char-table : (vector-of (union #f nat))
;; The lexer table, one entry per state per char.
;; Each entry specifies a state to transition to.
;; #f indicates no transition
(char-table (make-vector (* 256 (dfa-num-states dfa)) #f)))
;; Fill the char-table vector
(for-each
(lambda (trans)
(let ((from-state (car trans)))
(for-each (lambda (chars/to)
(let ((to-state (cdr chars/to)))
(loc:foldr (lambda (char _)
(vector-set! char-table
(bitwise-ior
char
(arithmetic-shift from-state 8))
to-state))
(void)
(car chars/to))))
(cdr trans))))
(dfa-transitions dfa))
char-table))
;; dfa->2d-table : dfa -> (same as build-lexer)
(define (dfa->2d-table dfa)
;; char-table : (vector-of (union #f nat))
;; The lexer table, one entry per state per char.
;; Each entry specifies a state to transition to.
;; #f indicates no transition
(define char-table (make-vector (* 256 (dfa-num-states dfa)) #f))
;; Fill the char-table vector
(for* ([trans (in-list (dfa-transitions dfa))]
[chars/to (in-list (cdr trans))])
(define from-state (car trans))
(define to-state (cdr chars/to))
(loc:foldr (λ (char _)
(vector-set! char-table
(bitwise-ior
char
(arithmetic-shift from-state 8))
to-state))
(void)
(car chars/to)))
char-table)
;; dfa->actions : dfa -> (vector-of (union #f syntax-object))
;; The action for each final state, #f if the state isn't final
(define (dfa->actions dfa)
(let ((actions (make-vector (dfa-num-states dfa) #f)))
(for-each (lambda (state/action)
(vector-set! actions (car state/action) (cdr state/action)))
(dfa-final-states/actions dfa))
actions))
;; dfa->actions : dfa -> (vector-of (union #f syntax-object))
;; The action for each final state, #f if the state isn't final
(define (dfa->actions dfa)
(define actions (make-vector (dfa-num-states dfa) #f))
(for ([state/action (in-list (dfa-final-states/actions dfa))])
(vector-set! actions (car state/action) (cdr state/action)))
actions)
;; dfa->no-look : dfa -> (vector-of bool)
;; For each state whether the lexer can ignore the next input.
;; It can do this only if there are no transitions out of the
;; current state.
(define (dfa->no-look dfa)
(let ((no-look (make-vector (dfa-num-states dfa) #t)))
(for-each (lambda (trans)
(vector-set! no-look (car trans) #f))
(dfa-transitions dfa))
no-look))
;; dfa->no-look : dfa -> (vector-of bool)
;; For each state whether the lexer can ignore the next input.
;; It can do this only if there are no transitions out of the
;; current state.
(define (dfa->no-look dfa)
(define no-look (make-vector (dfa-num-states dfa) #t))
(for ([trans (in-list (dfa-transitions dfa))])
(vector-set! no-look (car trans) #f))
no-look)
(test-block ((d1 (make-dfa 1 1 (list) (list)))
(d2 (make-dfa 4 1 (list (cons 2 2) (cons 3 3))
(list (cons 1 (list (cons (is:make-range 49 50) 1)
(cons (is:make-range 51) 2)))
(cons 2 (list (cons (is:make-range 49) 3))))))
(d3 (make-dfa 4 1 (list (cons 2 2) (cons 3 3))
(list (cons 1 (list (cons (is:make-range 100 200) 0)
(cons (is:make-range 49 50) 1)
(cons (is:make-range 51) 2)))
(cons 2 (list (cons (is:make-range 49) 3)))))))
((dfa->2d-table d1) (make-vector 256 #f))
((dfa->2d-table d2) (let ((v (make-vector 1024 #f)))
(vector-set! v 305 1)
(vector-set! v 306 1)
(vector-set! v 307 2)
(vector-set! v 561 3)
v))
((dfa->1d-table d1) (make-vector 1 #f))
((dfa->1d-table d2) #(#f
(test-block ((d1 (make-dfa 1 1 (list) (list)))
(d2 (make-dfa 4 1 (list (cons 2 2) (cons 3 3))
(list (cons 1 (list (cons (is:make-range 49 50) 1)
(cons (is:make-range 51) 2)))
(cons 2 (list (cons (is:make-range 49) 3))))))
(d3 (make-dfa 4 1 (list (cons 2 2) (cons 3 3))
(list (cons 1 (list (cons (is:make-range 100 200) 0)
(cons (is:make-range 49 50) 1)
(cons (is:make-range 51) 2)))
(cons 2 (list (cons (is:make-range 49) 3)))))))
((dfa->2d-table d1) (make-vector 256 #f))
((dfa->2d-table d2) (let ((v (make-vector 1024 #f)))
(vector-set! v 305 1)
(vector-set! v 306 1)
(vector-set! v 307 2)
(vector-set! v 561 3)
v))
((dfa->1d-table d1) (make-vector 1 #f))
((dfa->1d-table d2) #(#f
#(#(49 50 1) #(51 51 2))
#(#(49 49 3))
#f))
((dfa->1d-table d3) #(#f
((dfa->1d-table d3) #(#f
#(#(49 50 1) #(51 51 2) #(100 200 0))
#(#(49 49 3))
#f))
((dfa->actions d1) (vector #f))
((dfa->actions d2) (vector #f #f 2 3))
((dfa->no-look d1) (vector #t))
((dfa->no-look d2) (vector #t #f #f #t)))
;; build-lexer : syntax-object list ->
;; (values table nat (vector-of (union #f syntax-object)) (vector-of bool) (list-of syntax-object))
;; each syntax object has the form (re action)
(define (build-lexer sos)
(let* ((disappeared-uses (box null))
(s-re-acts (map (lambda (so)
(cons (parse (stx-car so) disappeared-uses)
(stx-car (stx-cdr so))))
sos))
((dfa->actions d1) (vector #f))
((dfa->actions d2) (vector #f #f 2 3))
((dfa->no-look d1) (vector #t))
((dfa->no-look d2) (vector #t #f #f #t)))
(cache (make-cache))
(re-acts (map (lambda (s-re-act)
(cons (->re (car s-re-act) cache)
(cdr s-re-act)))
s-re-acts))
(dfa (build-dfa re-acts cache))
(table (dfa->1d-table dfa)))
;(print-dfa dfa)
#;(let ((num-states (vector-length table))
(num-vectors (length (filter values (vector->list table))))
(num-entries (apply + (map
(lambda (x) (if x (vector-length x) 0))
(vector->list table))))
(num-different-entries
(let ((ht (make-hash-table)))
(for-each
(lambda (x)
(when x
(for-each
(lambda (y)
(hash-table-put! ht y #t))
(vector->list x))))
(vector->list table))
(length (hash-table-map ht cons)))))
(printf "~a states, ~aKB\n"
num-states
(/ (* 4.0 (+ 2 num-states (* 2 num-vectors) num-entries
(* 5 num-different-entries))) 1024)))
(values table (dfa-start-state dfa) (dfa->actions dfa) (dfa->no-look dfa)
(unbox disappeared-uses))))
)
;; build-lexer : syntax-object list ->
;; (values table nat (vector-of (union #f syntax-object)) (vector-of bool) (list-of syntax-object))
;; each syntax object has the form (re action)
(define (build-lexer sos)
(define disappeared-uses (box null))
(define s-re-acts (for/list ([so (in-list sos)])
(cons (parse (stx-car so) disappeared-uses)
(stx-car (stx-cdr so)))))
(define cache (make-cache))
(define re-acts (for/list ([s-re-act (in-list s-re-acts)])
(cons (->re (car s-re-act) cache)
(cdr s-re-act))))
(define dfa (build-dfa re-acts cache))
(define table (dfa->1d-table dfa))
;(print-dfa dfa)
#;(let ((num-states (vector-length table))
(num-vectors (length (filter values (vector->list table))))
(num-entries (apply + (map
(λ (x) (if x (vector-length x) 0))
(vector->list table))))
(num-different-entries
(let ((ht (make-hash)))
(for-each
(λ (x)
(when x
(for-each
(λ (y)
(hash-set! ht y #t))
(vector->list x))))
(vector->list table))
(length (hash-table-map ht cons)))))
(printf "~a states, ~aKB\n"
num-states
(/ (* 4.0 (+ 2 num-states (* 2 num-vectors) num-entries
(* 5 num-different-entries))) 1024)))
(values table (dfa-start-state dfa) (dfa->actions dfa) (dfa->no-look dfa)
(unbox disappeared-uses)))

@ -1,385 +1,384 @@
(module re mzscheme
(require mzlib/list
scheme/match
(prefix is: mzlib/integer-set)
"util.rkt")
#lang racket/base
(require racket/list
racket/match
(prefix-in is: data/integer-set)
"util.rkt")
(provide ->re build-epsilon build-zero build-char-set build-concat
build-repeat build-or build-and build-neg
epsilonR? zeroR? char-setR? concatR? repeatR? orR? andR? negR?
char-setR-chars concatR-re1 concatR-re2 repeatR-re repeatR-low repeatR-high
orR-res andR-res negR-re
re-nullable? re-index)
(provide ->re build-epsilon build-zero build-char-set build-concat
build-repeat build-or build-and build-neg
epsilonR? zeroR? char-setR? concatR? repeatR? orR? andR? negR?
char-setR-chars concatR-re1 concatR-re2 repeatR-re repeatR-low repeatR-high
orR-res andR-res negR-re
re-nullable? re-index)
;; get-index : -> nat
(define get-index (make-counter))
;; get-index : -> nat
(define get-index (make-counter))
;; An re is either
;; - (make-epsilonR bool nat)
;; - (make-zeroR bool nat)
;; - (make-char-setR bool nat char-set)
;; - (make-concatR bool nat re re)
;; - (make-repeatR bool nat nat nat-or-+inf.0 re)
;; - (make-orR bool nat (list-of re)) Must not directly contain any orRs
;; - (make-andR bool nat (list-of re)) Must not directly contain any andRs
;; - (make-negR bool nat re)
;;
;; Every re must have an index field globally different from all
;; other re index fields.
(define-struct re (nullable? index) (make-inspector))
(define-struct (epsilonR re) () (make-inspector))
(define-struct (zeroR re) () (make-inspector))
(define-struct (char-setR re) (chars) (make-inspector))
(define-struct (concatR re) (re1 re2) (make-inspector))
(define-struct (repeatR re) (low high re) (make-inspector))
(define-struct (orR re) (res) (make-inspector))
(define-struct (andR re) (res) (make-inspector))
(define-struct (negR re) (re) (make-inspector))
;; An re is either
;; - (make-epsilonR bool nat)
;; - (make-zeroR bool nat)
;; - (make-char-setR bool nat char-set)
;; - (make-concatR bool nat re re)
;; - (make-repeatR bool nat nat nat-or-+inf.0 re)
;; - (make-orR bool nat (list-of re)) Must not directly contain any orRs
;; - (make-andR bool nat (list-of re)) Must not directly contain any andRs
;; - (make-negR bool nat re)
;;
;; Every re must have an index field globally different from all
;; other re index fields.
(define-struct re (nullable? index) #:inspector (make-inspector))
(define-struct (epsilonR re) () #:inspector (make-inspector))
(define-struct (zeroR re) () #:inspector (make-inspector))
(define-struct (char-setR re) (chars) #:inspector (make-inspector))
(define-struct (concatR re) (re1 re2) #:inspector (make-inspector))
(define-struct (repeatR re) (low high re) #:inspector (make-inspector))
(define-struct (orR re) (res) #:inspector (make-inspector))
(define-struct (andR re) (res) #:inspector (make-inspector))
(define-struct (negR re) (re) #:inspector (make-inspector))
;; e : re
;; The unique epsilon re
(define e (make-epsilonR #t (get-index)))
;; e : re
;; The unique epsilon re
(define e (make-epsilonR #t (get-index)))
;; z : re
;; The unique zero re
(define z (make-zeroR #f (get-index)))
;; z : re
;; The unique zero re
(define z (make-zeroR #f (get-index)))
;; s-re = char constant
;; | string constant (sequence of characters)
;; | re a precompiled re
;; | (repetition low high s-re) repetition between low and high times (inclusive)
;; | (union s-re ...)
;; | (intersection s-re ...)
;; | (complement s-re)
;; | (concatenation s-re ...)
;; | (char-range rng rng) match any character between two (inclusive)
;; | (char-complement char-set) match any character not listed
;; low = natural-number
;; high = natural-number or +inf.0
;; rng = char or string with length 1
;; (concatenation) (repetition 0 0 x), and "" match the empty string.
;; (union) matches no strings.
;; (intersection) matches any string.
;; s-re = char constant
;; | string constant (sequence of characters)
;; | re a precompiled re
;; | (repetition low high s-re) repetition between low and high times (inclusive)
;; | (union s-re ...)
;; | (intersection s-re ...)
;; | (complement s-re)
;; | (concatenation s-re ...)
;; | (char-range rng rng) match any character between two (inclusive)
;; | (char-complement char-set) match any character not listed
;; low = natural-number
;; high = natural-number or +inf.0
;; rng = char or string with length 1
;; (concatenation) (repetition 0 0 x), and "" match the empty string.
;; (union) matches no strings.
;; (intersection) matches any string.
(define loc:make-range is:make-range)
(define loc:union is:union)
(define loc:split is:split)
(define loc:complement is:complement)
(define loc:make-range is:make-range)
(define loc:union is:union)
(define loc:split is:split)
(define loc:complement is:complement)
;; ->re : s-re cache -> re
(define (->re exp cache)
(match exp
((? char?) (build-char-set (loc:make-range (char->integer exp)) cache))
((? string?) (->re `(concatenation ,@(string->list exp)) cache))
((? re?) exp)
(`(repetition ,low ,high ,r)
(build-repeat low high (->re r cache) cache))
(`(union ,rs ...)
(build-or (flatten-res (map (lambda (r) (->re r cache)) rs)
orR? orR-res loc:union cache)
cache))
(`(intersection ,rs ...)
(build-and (flatten-res (map (lambda (r) (->re r cache)) rs)
andR? andR-res (lambda (a b)
(let-values (((i _ __) (loc:split a b))) i))
cache)
cache))
(`(complement ,r)
(build-neg (->re r cache) cache))
(`(concatenation ,rs ...)
(foldr (lambda (x y)
(build-concat (->re x cache) y cache))
e
rs))
(`(char-range ,c1 ,c2)
(let ((i1 (char->integer (if (string? c1) (string-ref c1 0) c1)))
(i2 (char->integer (if (string? c2) (string-ref c2 0) c2))))
(if (<= i1 i2)
(build-char-set (loc:make-range i1 i2) cache)
z)))
(`(char-complement ,crs ...)
(let ((cs (->re `(union ,@crs) cache)))
(cond
((zeroR? cs) (build-char-set (loc:make-range 0 max-char-num) cache))
((char-setR? cs)
(build-char-set (loc:complement (char-setR-chars cs) 0 max-char-num) cache))
(else z))))))
;; ->re : s-re cache -> re
(define (->re exp cache)
(match exp
[(? char?) (build-char-set (loc:make-range (char->integer exp)) cache)]
[(? string?) (->re `(concatenation ,@(string->list exp)) cache)]
[(? re?) exp]
[`(repetition ,low ,high ,r)
(build-repeat low high (->re r cache) cache)]
[`(union ,rs ...)
(build-or (flatten-res (map (λ (r) (->re r cache)) rs)
orR? orR-res loc:union cache)
cache)]
[`(intersection ,rs ...)
(build-and (flatten-res (map (λ (r) (->re r cache)) rs)
andR? andR-res (λ (a b)
(let-values (((i _ __) (loc:split a b))) i))
cache)
cache)]
[`(complement ,r) (build-neg (->re r cache) cache)]
[`(concatenation ,rs ...)
(foldr (λ (x y)
(build-concat (->re x cache) y cache))
e
rs)]
[`(char-range ,c1 ,c2)
(let ([i1 (char->integer (if (string? c1) (string-ref c1 0) c1))]
[i2 (char->integer (if (string? c2) (string-ref c2 0) c2))])
(if (<= i1 i2)
(build-char-set (loc:make-range i1 i2) cache)
z))]
[`(char-complement ,crs ...)
(let ([cs (->re `(union ,@crs) cache)])
(cond
[(zeroR? cs) (build-char-set (loc:make-range 0 max-char-num) cache)]
[(char-setR? cs)
(build-char-set (loc:complement (char-setR-chars cs) 0 max-char-num) cache)]
[else z]))]))
;; flatten-res: (list-of re) (re -> bool) (re -> (list-of re))
;; (char-set char-set -> char-set) cache -> (list-of re)
;; Takes all the char-sets in l and combines them into one char-set using the combine function.
;; Flattens out the values of type?. get-res only needs to function on things type? returns
;; true for.
(define (flatten-res l type? get-res combine cache)
(let loop ((res l)
;; chars : (union #f char-set)
(chars #f)
(no-chars null))
(cond
((null? res)
(if chars
(cons (build-char-set chars cache) no-chars)
no-chars))
((char-setR? (car res))
(if chars
(loop (cdr res) (combine (char-setR-chars (car res)) chars) no-chars)
(loop (cdr res) (char-setR-chars (car res)) no-chars)))
((type? (car res))
(loop (append (get-res (car res)) (cdr res)) chars no-chars))
(else (loop (cdr res) chars (cons (car res) no-chars))))))
;; flatten-res: (list-of re) (re -> bool) (re -> (list-of re))
;; (char-set char-set -> char-set) cache -> (list-of re)
;; Takes all the char-sets in l and combines them into one char-set using the combine function.
;; Flattens out the values of type?. get-res only needs to function on things type? returns
;; true for.
(define (flatten-res l type? get-res combine cache)
(let loop ([res l]
;; chars : (union #f char-set)
[chars #f]
[no-chars null])
(cond
[(null? res)
(if chars
(cons (build-char-set chars cache) no-chars)
no-chars)]
[(char-setR? (car res))
(if chars
(loop (cdr res) (combine (char-setR-chars (car res)) chars) no-chars)
(loop (cdr res) (char-setR-chars (car res)) no-chars))]
[(type? (car res))
(loop (append (get-res (car res)) (cdr res)) chars no-chars)]
[else (loop (cdr res) chars (cons (car res) no-chars))])))
;; build-epsilon : -> re
(define (build-epsilon) e)
;; build-epsilon : -> re
(define (build-epsilon) e)
(define (build-zero) z)
(define (build-zero) z)
(define loc:integer-set-contents is:integer-set-contents)
(define loc:integer-set-contents is:integer-set-contents)
;; build-char-set : char-set cache -> re
(define (build-char-set cs cache)
(let ((l (loc:integer-set-contents cs)))
(cond
((null? l) z)
(else
(cache l
(lambda ()
(make-char-setR #f (get-index) cs)))))))
;; build-char-set : char-set cache -> re
(define (build-char-set cs cache)
(define l (loc:integer-set-contents cs))
(cond
[(null? l) z]
[else
(cache l
(λ ()
(make-char-setR #f (get-index) cs)))]))
;; build-concat : re re cache -> re
(define (build-concat r1 r2 cache)
(cond
((eq? e r1) r2)
((eq? e r2) r1)
((or (eq? z r1) (eq? z r2)) z)
(else
(cache (cons 'concat (cons (re-index r1) (re-index r2)))
(lambda ()
(make-concatR (and (re-nullable? r1) (re-nullable? r2))
(get-index)
r1 r2))))))
;; build-concat : re re cache -> re
(define (build-concat r1 r2 cache)
(cond
[(eq? e r1) r2]
[(eq? e r2) r1]
[(or (eq? z r1) (eq? z r2)) z]
[else
(cache (cons 'concat (cons (re-index r1) (re-index r2)))
(λ ()
(make-concatR (and (re-nullable? r1) (re-nullable? r2))
(get-index)
r1 r2)))]))
;; build-repeat : nat nat-or-+inf.0 re cache -> re
(define (build-repeat low high r cache)
(let ((low (if (< low 0) 0 low)))
(cond
((eq? r e) e)
((and (= 0 low) (or (= 0 high) (eq? z r))) e)
((and (= 1 low) (= 1 high)) r)
((and (repeatR? r)
(eqv? (repeatR-high r) +inf.0)
(or (= 0 (repeatR-low r))
(= 1 (repeatR-low r))))
(build-repeat (* low (repeatR-low r))
+inf.0
(repeatR-re r)
cache))
(else
(cache (cons 'repeat (cons low (cons high (re-index r))))
(lambda ()
(make-repeatR (or (re-nullable? r) (= 0 low)) (get-index) low high r)))))))
;; build-repeat : nat nat-or-+inf.0 re cache -> re
(define (build-repeat low high r cache)
(let ([low (if (< low 0) 0 low)])
(cond
[(eq? r e) e]
[(and (= 0 low) (or (= 0 high) (eq? z r))) e]
[(and (= 1 low) (= 1 high)) r]
[(and (repeatR? r)
(eqv? (repeatR-high r) +inf.0)
(or (= 0 (repeatR-low r))
(= 1 (repeatR-low r))))
(build-repeat (* low (repeatR-low r))
+inf.0
(repeatR-re r)
cache)]
[else
(cache (cons 'repeat (cons low (cons high (re-index r))))
(λ ()
(make-repeatR (or (re-nullable? r) (= 0 low)) (get-index) low high r)))])))
;; build-or : (list-of re) cache -> re
(define (build-or rs cache)
(let ((rs
(filter
(lambda (x) (not (eq? x z)))
(do-simple-equiv (replace rs orR? orR-res null) re-index))))
(cond
((null? rs) z)
((null? (cdr rs)) (car rs))
((memq (build-neg z cache) rs) (build-neg z cache))
(else
(cache (cons 'or (map re-index rs))
(lambda ()
(make-orR (ormap re-nullable? rs) (get-index) rs)))))))
;; build-or : (list-of re) cache -> re
(define (build-or rs cache)
(let ([rs
(filter
(λ (x) (not (eq? x z)))
(do-simple-equiv (replace rs orR? orR-res null) re-index))])
(cond
[(null? rs) z]
[(null? (cdr rs)) (car rs)]
[(memq (build-neg z cache) rs) (build-neg z cache)]
[else
(cache (cons 'or (map re-index rs))
(λ ()
(make-orR (ormap re-nullable? rs) (get-index) rs)))])))
;; build-and : (list-of re) cache -> re
(define (build-and rs cache)
(let ((rs (do-simple-equiv (replace rs andR? andR-res null) re-index)))
(cond
((null? rs) (build-neg z cache))
((null? (cdr rs)) (car rs))
((memq z rs) z)
(else
(cache (cons 'and (map re-index rs))
(lambda ()
(make-andR (andmap re-nullable? rs) (get-index) rs)))))))
;; build-neg : re cache -> re
(define (build-neg r cache)
;; build-and : (list-of re) cache -> re
(define (build-and rs cache)
(let ([rs (do-simple-equiv (replace rs andR? andR-res null) re-index)])
(cond
((negR? r) (negR-re r))
(else
(cache (cons 'neg (re-index r))
(lambda ()
(make-negR (not (re-nullable? r)) (get-index) r))))))
[(null? rs) (build-neg z cache)]
[(null? (cdr rs)) (car rs)]
[(memq z rs) z]
[else
(cache (cons 'and (map re-index rs))
(λ ()
(make-andR (andmap re-nullable? rs) (get-index) rs)))])))
;; build-neg : re cache -> re
(define (build-neg r cache)
(cond
[(negR? r) (negR-re r)]
[else
(cache (cons 'neg (re-index r))
(λ ()
(make-negR (not (re-nullable? r)) (get-index) r)))]))
;; Tests for the build-functions
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r1 (build-char-set (is:make-range (char->integer #\1)) c))
(r2 (build-char-set (is:make-range (char->integer #\2)) c))
(r3 (build-char-set (is:make-range (char->integer #\3)) c))
(rc (build-concat r1 r2 c))
(rc2 (build-concat r2 r1 c))
(rr (build-repeat 0 +inf.0 rc c))
(ro (build-or `(,rr ,rc ,rr) c))
(ro2 (build-or `(,rc ,rr ,z) c))
(ro3 (build-or `(,rr ,rc) c))
(ro4 (build-or `(,(build-or `(,r1 ,r2) c)
,(build-or `(,r2 ,r3) c)) c))
(ra (build-and `(,rr ,rc ,rr) c))
(ra2 (build-and `(,rc ,rr) c))
(ra3 (build-and `(,rr ,rc) c))
(ra4 (build-and `(,(build-and `(,r3 ,r2) c)
,(build-and `(,r2 ,r1) c)) c))
(rn (build-neg z c))
(rn2 (build-neg r1 c)))
;; Tests for the build-functions
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r1 (build-char-set (is:make-range (char->integer #\1)) c))
(r2 (build-char-set (is:make-range (char->integer #\2)) c))
(r3 (build-char-set (is:make-range (char->integer #\3)) c))
(rc (build-concat r1 r2 c))
(rc2 (build-concat r2 r1 c))
(rr (build-repeat 0 +inf.0 rc c))
(ro (build-or `(,rr ,rc ,rr) c))
(ro2 (build-or `(,rc ,rr ,z) c))
(ro3 (build-or `(,rr ,rc) c))
(ro4 (build-or `(,(build-or `(,r1 ,r2) c)
,(build-or `(,r2 ,r3) c)) c))
(ra (build-and `(,rr ,rc ,rr) c))
(ra2 (build-and `(,rc ,rr) c))
(ra3 (build-and `(,rr ,rc) c))
(ra4 (build-and `(,(build-and `(,r3 ,r2) c)
,(build-and `(,r2 ,r1) c)) c))
(rn (build-neg z c))
(rn2 (build-neg r1 c)))
((isc (char-setR-chars r1)) (isc (is:make-range (char->integer #\1))))
((isc (char-setR-chars r2)) (isc (is:make-range (char->integer #\2))))
((isc (char-setR-chars r3)) (isc (is:make-range (char->integer #\3))))
((build-char-set (is:make-range) c) z)
((build-concat r1 e c) r1)
((build-concat e r1 c) r1)
((build-concat r1 z c) z)
((build-concat z r1 c) z)
((build-concat r1 r2 c) rc)
((concatR-re1 rc) r1)
((concatR-re2 rc) r2)
((concatR-re1 rc2) r2)
((concatR-re2 rc2) r1)
(ro ro2)
(ro ro3)
(ro4 (build-or `(,r1 ,r2 ,r3) c))
((orR-res ro) (list rc rr))
((orR-res ro4) (list r1 r2 r3))
((build-or null c) z)
((build-or `(,r1 ,z) c) r1)
((build-repeat 0 +inf.0 rc c) rr)
((build-repeat 0 1 z c) e)
((build-repeat 0 0 rc c) e)
((build-repeat 0 +inf.0 z c) e)
((build-repeat -1 +inf.0 z c) e)
((build-repeat 0 +inf.0 (build-repeat 0 +inf.0 rc c) c)
(build-repeat 0 +inf.0 rc c))
((build-repeat 20 20 (build-repeat 0 +inf.0 rc c) c)
(build-repeat 0 +inf.0 rc c))
((build-repeat 20 20 (build-repeat 1 +inf.0 rc c) c)
(build-repeat 20 +inf.0 rc c))
((build-repeat 1 1 rc c) rc)
((repeatR-re rr) rc)
(ra ra2)
(ra ra3)
(ra4 (build-and `(,r1 ,r2 ,r3) c))
((andR-res ra) (list rc rr))
((andR-res ra4) (list r1 r2 r3))
((build-and null c) (build-neg z c))
((build-and `(,r1 ,z) c) z)
((build-and `(,r1) c) r1)
((build-neg r1 c) (build-neg r1 c))
((build-neg (build-neg r1 c) c) r1)
((negR-re (build-neg r2 c)) r2)
((re-nullable? r1) #f)
((re-nullable? rc) #f)
((re-nullable? (build-concat rr rr c)) #t)
((re-nullable? rr) #t)
((re-nullable? (build-repeat 0 1 rc c)) #t)
((re-nullable? (build-repeat 1 2 rc c)) #f)
((re-nullable? (build-repeat 1 2 (build-or (list e r1) c) c)) #t)
((re-nullable? ro) #t)
((re-nullable? (build-or `(,r1 ,r2) c)) #f)
((re-nullable? (build-and `(,r1 ,e) c)) #f)
((re-nullable? (build-and `(,rr ,e) c)) #t)
((re-nullable? (build-neg r1 c)) #t)
((re-nullable? (build-neg rr c)) #f))
((isc (char-setR-chars r1)) (isc (is:make-range (char->integer #\1))))
((isc (char-setR-chars r2)) (isc (is:make-range (char->integer #\2))))
((isc (char-setR-chars r3)) (isc (is:make-range (char->integer #\3))))
((build-char-set (is:make-range) c) z)
((build-concat r1 e c) r1)
((build-concat e r1 c) r1)
((build-concat r1 z c) z)
((build-concat z r1 c) z)
((build-concat r1 r2 c) rc)
((concatR-re1 rc) r1)
((concatR-re2 rc) r2)
((concatR-re1 rc2) r2)
((concatR-re2 rc2) r1)
(ro ro2)
(ro ro3)
(ro4 (build-or `(,r1 ,r2 ,r3) c))
((orR-res ro) (list rc rr))
((orR-res ro4) (list r1 r2 r3))
((build-or null c) z)
((build-or `(,r1 ,z) c) r1)
((build-repeat 0 +inf.0 rc c) rr)
((build-repeat 0 1 z c) e)
((build-repeat 0 0 rc c) e)
((build-repeat 0 +inf.0 z c) e)
((build-repeat -1 +inf.0 z c) e)
((build-repeat 0 +inf.0 (build-repeat 0 +inf.0 rc c) c)
(build-repeat 0 +inf.0 rc c))
((build-repeat 20 20 (build-repeat 0 +inf.0 rc c) c)
(build-repeat 0 +inf.0 rc c))
((build-repeat 20 20 (build-repeat 1 +inf.0 rc c) c)
(build-repeat 20 +inf.0 rc c))
((build-repeat 1 1 rc c) rc)
((repeatR-re rr) rc)
(ra ra2)
(ra ra3)
(ra4 (build-and `(,r1 ,r2 ,r3) c))
((andR-res ra) (list rc rr))
((andR-res ra4) (list r1 r2 r3))
((build-and null c) (build-neg z c))
((build-and `(,r1 ,z) c) z)
((build-and `(,r1) c) r1)
((build-neg r1 c) (build-neg r1 c))
((build-neg (build-neg r1 c) c) r1)
((negR-re (build-neg r2 c)) r2)
((re-nullable? r1) #f)
((re-nullable? rc) #f)
((re-nullable? (build-concat rr rr c)) #t)
((re-nullable? rr) #t)
((re-nullable? (build-repeat 0 1 rc c)) #t)
((re-nullable? (build-repeat 1 2 rc c)) #f)
((re-nullable? (build-repeat 1 2 (build-or (list e r1) c) c)) #t)
((re-nullable? ro) #t)
((re-nullable? (build-or `(,r1 ,r2) c)) #f)
((re-nullable? (build-and `(,r1 ,e) c)) #f)
((re-nullable? (build-and `(,rr ,e) c)) #t)
((re-nullable? (build-neg r1 c)) #t)
((re-nullable? (build-neg rr c)) #f))
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r1 (->re #\1 c))
(r2 (->re #\2 c))
(r3-5 (->re '(char-range #\3 #\5) c))
(r4 (build-or `(,r1 ,r2) c))
(r5 (->re `(union ,r3-5 #\7) c))
(r6 (->re #\6 c)))
((flatten-res null orR? orR-res is:union c) null)
((isc (char-setR-chars (car (flatten-res `(,r1) orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1))))
((isc (char-setR-chars (car (flatten-res `(,r4) orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1) (char->integer #\2))))
((isc (char-setR-chars (car (flatten-res `(,r6 ,r5 ,r4 ,r3-5 ,r2 ,r1)
orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1) (char->integer #\7))))
((flatten-res `(,r1 ,r2) andR? andR-res (lambda (x y)
(let-values (((i _ __)
(is:split x y)))
i))
c)
(list z)))
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r1 (->re #\1 c))
(r2 (->re #\2 c))
(r3-5 (->re '(char-range #\3 #\5) c))
(r4 (build-or `(,r1 ,r2) c))
(r5 (->re `(union ,r3-5 #\7) c))
(r6 (->re #\6 c)))
((flatten-res null orR? orR-res is:union c) null)
((isc (char-setR-chars (car (flatten-res `(,r1) orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1))))
((isc (char-setR-chars (car (flatten-res `(,r4) orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1) (char->integer #\2))))
((isc (char-setR-chars (car (flatten-res `(,r6 ,r5 ,r4 ,r3-5 ,r2 ,r1)
orR? orR-res is:union c))))
(isc (is:make-range (char->integer #\1) (char->integer #\7))))
((flatten-res `(,r1 ,r2) andR? andR-res (λ (x y)
(let-values (((i _ __)
(is:split x y)))
i))
c)
(list z)))
;; ->re
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r (->re #\a c))
(rr (->re `(concatenation ,r ,r) c))
(rrr (->re `(concatenation ,r ,rr) c))
(rrr* (->re `(repetition 0 +inf.0 ,rrr) c)))
((isc (char-setR-chars r)) (isc (is:make-range (char->integer #\a))))
((->re "" c) e)
((->re "asdf" c) (->re `(concatenation #\a #\s #\d #\f) c))
((->re r c) r)
((->re `(repetition 0 +inf.0 ,r) c) (build-repeat 0 +inf.0 r c))
((->re `(repetition 1 +inf.0 ,r) c) (build-repeat 1 +inf.0 r c))
((->re `(repetition 0 1 ,r) c) (build-repeat 0 1 r c))
((->re `(repetition 0 1 ,rrr*) c) rrr*)
((->re `(union (union (char-range #\a #\c)
(char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(union (repetition 0 +inf.0 #\2))) c)
(build-or (list (build-char-set (is:union (is:make-range 73)
(is:make-range 97 99))
c)
(build-repeat 0 +inf.0 (build-char-set (is:make-range 50) c) c))
c))
((->re `(union ,rr ,rrr) c) (build-or (list rr rrr) c))
((->re `(union ,r) c) r)
((->re `(union) c) z)
((->re `(intersection (intersection #\111
(char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(intersection (repetition 0 +inf.0 #\2))) c)
(build-and (list (build-char-set (is:make-range 73) c)
(build-repeat 0 +inf.0 (build-char-set (is:make-range 50) c) c))
c))
((->re `(intersection (intersection #\000 (char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(intersection (repetition 0 +inf.0 #\2))) c)
z)
((->re `(intersection ,rr ,rrr) c) (build-and (list rr rrr) c))
((->re `(intersection ,r) c) r)
((->re `(intersection) c) (build-neg z c))
((->re `(complement ,r) c) (build-neg r c))
((->re `(concatenation) c) e)
((->re `(concatenation ,rrr*) c) rrr*)
(rr (build-concat r r c))
((->re `(concatenation ,r ,rr ,rrr) c)
(build-concat r (build-concat rr rrr c) c))
((isc (char-setR-chars (->re `(char-range #\1 #\1) c))) (isc (is:make-range 49)))
((isc (char-setR-chars (->re `(char-range #\1 #\9) c))) (isc (is:make-range 49 57)))
((isc (char-setR-chars (->re `(char-range "1" "1") c))) (isc (is:make-range 49)))
((isc (char-setR-chars (->re `(char-range "1" "9") c))) (isc (is:make-range 49 57)))
((->re `(char-range "9" "1") c) z)
((isc (char-setR-chars (->re `(char-complement) c)))
(isc (char-setR-chars (->re `(char-range #\000 ,(integer->char max-char-num)) c))))
((isc (char-setR-chars (->re `(char-complement #\001 (char-range #\002 ,(integer->char max-char-num))) c)))
(isc (is:make-range 0)))
)
;; ->re
(test-block ((c (make-cache))
(isc is:integer-set-contents)
(r (->re #\a c))
(rr (->re `(concatenation ,r ,r) c))
(rrr (->re `(concatenation ,r ,rr) c))
(rrr* (->re `(repetition 0 +inf.0 ,rrr) c)))
((isc (char-setR-chars r)) (isc (is:make-range (char->integer #\a))))
((->re "" c) e)
((->re "asdf" c) (->re `(concatenation #\a #\s #\d #\f) c))
((->re r c) r)
((->re `(repetition 0 +inf.0 ,r) c) (build-repeat 0 +inf.0 r c))
((->re `(repetition 1 +inf.0 ,r) c) (build-repeat 1 +inf.0 r c))
((->re `(repetition 0 1 ,r) c) (build-repeat 0 1 r c))
((->re `(repetition 0 1 ,rrr*) c) rrr*)
((->re `(union (union (char-range #\a #\c)
(char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(union (repetition 0 +inf.0 #\2))) c)
(build-or (list (build-char-set (is:union (is:make-range 73)
(is:make-range 97 99))
c)
(build-repeat 0 +inf.0 (build-char-set (is:make-range 50) c) c))
c))
((->re `(union ,rr ,rrr) c) (build-or (list rr rrr) c))
((->re `(union ,r) c) r)
((->re `(union) c) z)
((->re `(intersection (intersection #\111
(char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(intersection (repetition 0 +inf.0 #\2))) c)
(build-and (list (build-char-set (is:make-range 73) c)
(build-repeat 0 +inf.0 (build-char-set (is:make-range 50) c) c))
c))
((->re `(intersection (intersection #\000 (char-complement (char-range #\000 #\110)
(char-range #\112 ,(integer->char max-char-num))))
(intersection (repetition 0 +inf.0 #\2))) c)
z)
((->re `(intersection ,rr ,rrr) c) (build-and (list rr rrr) c))
((->re `(intersection ,r) c) r)
((->re `(intersection) c) (build-neg z c))
((->re `(complement ,r) c) (build-neg r c))
((->re `(concatenation) c) e)
((->re `(concatenation ,rrr*) c) rrr*)
(rr (build-concat r r c))
((->re `(concatenation ,r ,rr ,rrr) c)
(build-concat r (build-concat rr rrr c) c))
((isc (char-setR-chars (->re `(char-range #\1 #\1) c))) (isc (is:make-range 49)))
((isc (char-setR-chars (->re `(char-range #\1 #\9) c))) (isc (is:make-range 49 57)))
((isc (char-setR-chars (->re `(char-range "1" "1") c))) (isc (is:make-range 49)))
((isc (char-setR-chars (->re `(char-range "1" "9") c))) (isc (is:make-range 49 57)))
((->re `(char-range "9" "1") c) z)
((isc (char-setR-chars (->re `(char-complement) c)))
(isc (char-setR-chars (->re `(char-range #\000 ,(integer->char max-char-num)) c))))
((isc (char-setR-chars (->re `(char-complement #\001 (char-range #\002 ,(integer->char max-char-num))) c)))
(isc (is:make-range 0)))
)
)

@ -1,30 +1,25 @@
#lang racket
(require "util.rkt"
syntax/id-table)
#lang racket/base
(require "util.rkt" syntax/id-table)
(provide parse)
(define (bad-args stx num)
(raise-syntax-error
#f
(format "incorrect number of arguments (should have ~a)" num)
stx))
(raise-syntax-error #f (format "incorrect number of arguments (should have ~a)" num) stx))
;; char-range-arg: syntax-object syntax-object -> nat
;; If c contains is a character or length 1 string, returns the integer
;; for the character. Otherwise raises a syntax error.
(define (char-range-arg stx containing-stx)
(let ((c (syntax-e stx)))
(cond
((char? c) (char->integer c))
((and (string? c) (= (string-length c) 1))
(char->integer (string-ref c 0)))
(else
(raise-syntax-error
#f
"not a char or single-char string"
containing-stx stx)))))
(define c (syntax-e stx))
(cond
[(char? c) (char->integer c)]
[(and (string? c) (= (string-length c) 1))
(char->integer (string-ref c 0))]
[else
(raise-syntax-error
#f
"not a char or single-char string"
containing-stx stx)]))
(module+ test
(check-equal? (char-range-arg #'#\1 #'here) (char->integer #\1))
(check-equal? (char-range-arg #'"1" #'here) (char->integer #\1)))
@ -34,187 +29,157 @@
(define (disarm stx)
(syntax-disarm stx orig-insp))
;; parse : syntax-object (box (list-of syntax-object)) -> s-re (see re.rkt)
;; checks for errors and generates the plain s-exp form for s
;; Expands lex-abbrevs and applies lex-trans.
(define (parse stx disappeared-uses)
(let loop ([stx stx]
[disappeared-uses disappeared-uses]
;; seen-lex-abbrevs: id-table
[seen-lex-abbrevs (make-immutable-free-id-table)])
(let ([recur (lambda (s)
(loop (syntax-rearm s stx)
disappeared-uses
seen-lex-abbrevs))]
[recur/abbrev (lambda (s id)
(loop (syntax-rearm s stx)
disappeared-uses
(free-id-table-set seen-lex-abbrevs id id)))])
(syntax-case (disarm stx) (repetition union intersection complement concatenation
char-range char-complement)
(_
(identifier? stx)
(let ((expansion (syntax-local-value stx (lambda () #f))))
(unless (lex-abbrev? expansion)
(raise-syntax-error 'regular-expression
"undefined abbreviation"
stx))
;; Check for cycles.
(when (free-id-table-ref seen-lex-abbrevs stx (lambda () #f))
(raise-syntax-error 'regular-expression
"illegal lex-abbrev cycle detected"
stx
#f
(list (free-id-table-ref seen-lex-abbrevs stx))))
(set-box! disappeared-uses (cons stx (unbox disappeared-uses)))
(recur/abbrev ((lex-abbrev-get-abbrev expansion)) stx)))
(_
(or (char? (syntax-e stx)) (string? (syntax-e stx)))
(syntax-e stx))
((repetition arg ...)
(let ((arg-list (syntax->list (syntax (arg ...)))))
(unless (= 3 (length arg-list))
(bad-args stx 2))
(let ((low (syntax-e (car arg-list)))
(high (syntax-e (cadr arg-list)))
(re (caddr arg-list)))
(unless (and (number? low) (exact? low) (integer? low) (>= low 0))
(raise-syntax-error #f
"not a non-negative exact integer"
stx
(car arg-list)))
(unless (or (and (number? high) (exact? high) (integer? high) (>= high 0))
(eqv? high +inf.0))
(raise-syntax-error #f
"not a non-negative exact integer or +inf.0"
stx
(cadr arg-list)))
(unless (<= low high)
(raise-syntax-error
#f
"the first argument is not less than or equal to the second argument"
stx))
`(repetition ,low ,high ,(recur re)))))
((union re ...)
`(union ,@(map recur (syntax->list (syntax (re ...))))))
((intersection re ...)
`(intersection ,@(map recur (syntax->list (syntax (re ...))))))
((complement re ...)
(let ((re-list (syntax->list (syntax (re ...)))))
(unless (= 1 (length re-list))
(bad-args stx 1))
`(complement ,(recur (car re-list)))))
((concatenation re ...)
`(concatenation ,@(map recur (syntax->list (syntax (re ...))))))
((char-range arg ...)
(let ((arg-list (syntax->list (syntax (arg ...)))))
(unless (= 2 (length arg-list))
(bad-args stx 2))
(let ((i1 (char-range-arg (car arg-list) stx))
(i2 (char-range-arg (cadr arg-list) stx)))
(if (<= i1 i2)
`(char-range ,(integer->char i1) ,(integer->char i2))
(raise-syntax-error
#f
"the first argument does not precede or equal second argument"
stx)))))
((char-complement arg ...)
(let ((arg-list (syntax->list (syntax (arg ...)))))
(unless (= 1 (length arg-list))
(bad-args stx 1))
(let ((parsed (recur (car arg-list))))
(unless (char-set? parsed)
(raise-syntax-error #f
"not a character set"
stx
(car arg-list)))
`(char-complement ,parsed))))
((op form ...)
(identifier? (syntax op))
(let* ((o (syntax op))
(expansion (syntax-local-value o (lambda () #f))))
(set-box! disappeared-uses (cons o (unbox disappeared-uses)))
(cond
((lex-trans? expansion)
(recur ((lex-trans-f expansion) (disarm stx))))
(expansion
(raise-syntax-error 'regular-expression
"not a lex-trans"
stx))
(else
(raise-syntax-error 'regular-expression
"undefined operator"
stx)))))
(_
(raise-syntax-error
'regular-expression
"not a char, string, identifier, or (op args ...)"
stx))))))
;; parse : syntax-object (box (list-of syntax-object)) -> s-re (see re.rkt)
;; checks for errors and generates the plain s-exp form for s
;; Expands lex-abbrevs and applies lex-trans.
(define (parse stx disappeared-uses)
(let loop ([stx stx]
[disappeared-uses disappeared-uses]
;; seen-lex-abbrevs: id-table
[seen-lex-abbrevs (make-immutable-free-id-table)])
(let ([recur (λ (s)
(loop (syntax-rearm s stx)
disappeared-uses
seen-lex-abbrevs))]
[recur/abbrev (λ (s id)
(loop (syntax-rearm s stx)
disappeared-uses
(free-id-table-set seen-lex-abbrevs id id)))])
(syntax-case (disarm stx) (repetition union intersection complement concatenation
char-range char-complement)
[_
(identifier? stx)
(let ([expansion (syntax-local-value stx (λ () #f))])
(unless (lex-abbrev? expansion)
(raise-syntax-error 'regular-expression
"undefined abbreviation"
stx))
;; Check for cycles.
(when (free-id-table-ref seen-lex-abbrevs stx (λ () #f))
(raise-syntax-error 'regular-expression
"illegal lex-abbrev cycle detected"
stx
#f
(list (free-id-table-ref seen-lex-abbrevs stx))))
(set-box! disappeared-uses (cons stx (unbox disappeared-uses)))
(recur/abbrev ((lex-abbrev-get-abbrev expansion)) stx))]
[_
(or (char? (syntax-e stx)) (string? (syntax-e stx)))
(syntax-e stx)]
[(repetition ARG ...)
(let ([arg-list (syntax->list #'(ARG ...))])
(unless (= 3 (length arg-list))
(bad-args stx 2))
(define low (syntax-e (car arg-list)))
(define high (syntax-e (cadr arg-list)))
(define re (caddr arg-list))
(unless (and (number? low) (exact? low) (integer? low) (>= low 0))
(raise-syntax-error #f "not a non-negative exact integer" stx (car arg-list)))
(unless (or (and (number? high) (exact? high) (integer? high) (>= high 0))
(eqv? high +inf.0))
(raise-syntax-error #f "not a non-negative exact integer or +inf.0" stx (cadr arg-list)))
(unless (<= low high)
(raise-syntax-error #f "the first argument is not less than or equal to the second argument" stx))
`(repetition ,low ,high ,(recur re)))]
[(union RE ...)
`(union ,@(map recur (syntax->list #'(RE ...))))]
[(intersection RE ...)
`(intersection ,@(map recur (syntax->list #'(RE ...))))]
[(complement RE ...)
(let ([re-list (syntax->list #'(RE ...))])
(unless (= 1 (length re-list))
(bad-args stx 1))
`(complement ,(recur (car re-list))))]
[(concatenation RE ...)
`(concatenation ,@(map recur (syntax->list #'(RE ...))))]
[(char-range ARG ...)
(let ((arg-list (syntax->list #'(ARG ...))))
(unless (= 2 (length arg-list))
(bad-args stx 2))
(let ([i1 (char-range-arg (car arg-list) stx)]
[i2 (char-range-arg (cadr arg-list) stx)])
(if (<= i1 i2)
`(char-range ,(integer->char i1) ,(integer->char i2))
(raise-syntax-error #f "the first argument does not precede or equal second argument" stx))))]
[(char-complement ARG ...)
(let ([arg-list (syntax->list #'(ARG ...))])
(unless (= 1 (length arg-list))
(bad-args stx 1))
(define parsed (recur (car arg-list)))
(unless (char-set? parsed)
(raise-syntax-error #f "not a character set" stx (car arg-list)))
`(char-complement ,parsed))]
((OP form ...)
(identifier? #'OP)
(let* ([expansion (syntax-local-value #'OP (λ () #f))])
(set-box! disappeared-uses (cons #'OP (unbox disappeared-uses)))
(cond
[(lex-trans? expansion)
(recur ((lex-trans-f expansion) (disarm stx)))]
[expansion
(raise-syntax-error 'regular-expression "not a lex-trans" stx)]
[else
(raise-syntax-error 'regular-expression "undefined operator" stx)])))
[_ (raise-syntax-error 'regular-expression "not a char, string, identifier, or (op args ...)" stx)]))))
;; char-set? : s-re -> bool
;; A char-set is an re that matches only strings of length 1.
;; char-set? is conservative.
(define (char-set? s-re)
(cond
((char? s-re) #t)
((string? s-re) (= (string-length s-re) 1))
((list? s-re)
(let ((op (car s-re)))
(case op
((union intersection) (andmap char-set? (cdr s-re)))
((char-range char-complement) #t)
((repetition)
(and (= (cadr s-re) (caddr s-re)) (char-set? (cadddr s-re))))
((concatenation)
(and (= 2 (length s-re)) (char-set? (cadr s-re))))
(else #f))))
(else #f)))
;; char-set? : s-re -> bool
;; A char-set is an re that matches only strings of length 1.
;; char-set? is conservative.
(define (char-set? s-re)
(cond
[(char? s-re)]
[(string? s-re) (= (string-length s-re) 1)]
[(list? s-re) (case (car s-re)
[(union intersection) (andmap char-set? (cdr s-re))]
[(char-range char-complement) #t]
[(repetition) (and (= (cadr s-re) (caddr s-re)) (char-set? (cadddr s-re)))]
[(concatenation) (and (= 2 (length s-re)) (char-set? (cadr s-re)))]
(else #f))]
[else #f]))
(module+ test
(require rackunit))
(module+ test
(check-equal? (char-set? #\a) #t)
(check-equal? (char-set? "12") #f)
(check-equal? (char-set? "1") #t)
(check-equal? (char-set? '(repetition 1 2 #\1)) #f)
(check-equal? (char-set? '(repetition 1 1 "12")) #f)
(check-equal? (char-set? '(repetition 1 1 "1")) #t)
(check-equal? (char-set? '(union "1" "2" "3")) #t)
(check-equal? (char-set? '(union "1" "" "3")) #f)
(check-equal? (char-set? '(intersection "1" "2" (union "3" "4"))) #t)
(check-equal? (char-set? '(intersection "1" "")) #f)
(check-equal? (char-set? '(complement "1")) #f)
(check-equal? (char-set? '(concatenation "1" "2")) #f)
(check-equal? (char-set? '(concatenation "" "2")) #f)
(check-equal? (char-set? '(concatenation "1")) #t)
(check-equal? (char-set? '(concatenation "12")) #f)
(check-equal? (char-set? '(char-range #\1 #\2)) #t)
(check-equal? (char-set? '(char-complement #\1)) #t))
(module+ test
(require rackunit)
(check-equal? (char-set? #\a) #t)
(check-equal? (char-set? "12") #f)
(check-equal? (char-set? "1") #t)
(check-equal? (char-set? '(repetition 1 2 #\1)) #f)
(check-equal? (char-set? '(repetition 1 1 "12")) #f)
(check-equal? (char-set? '(repetition 1 1 "1")) #t)
(check-equal? (char-set? '(union "1" "2" "3")) #t)
(check-equal? (char-set? '(union "1" "" "3")) #f)
(check-equal? (char-set? '(intersection "1" "2" (union "3" "4"))) #t)
(check-equal? (char-set? '(intersection "1" "")) #f)
(check-equal? (char-set? '(complement "1")) #f)
(check-equal? (char-set? '(concatenation "1" "2")) #f)
(check-equal? (char-set? '(concatenation "" "2")) #f)
(check-equal? (char-set? '(concatenation "1")) #t)
(check-equal? (char-set? '(concatenation "12")) #f)
(check-equal? (char-set? '(char-range #\1 #\2)) #t)
(check-equal? (char-set? '(char-complement #\1)) #t))
;; yikes... these test cases all have the wrong arity, now.
;; and by "now", I mean it's been broken since before we
;; moved to git.
(module+ test
(check-equal? (parse #'#\a null) #\a)
(check-equal? (parse #'"1" null) "1")
(check-equal? (parse #'(repetition 1 1 #\1) null)
'(repetition 1 1 #\1))
(check-equal? (parse #'(repetition 0 +inf.0 #\1) null) '(repetition 0 +inf.0 #\1))
(check-equal? (parse #'(union #\1 (union "2") (union)) null)
'(union #\1 (union "2") (union)))
(check-equal? (parse #'(intersection #\1 (intersection "2") (intersection))
null)
'(intersection #\1 (intersection "2") (intersection)))
(check-equal? (parse #'(complement (union #\1 #\2))
null)
'(complement (union #\1 #\2)))
(check-equal? (parse #'(concatenation "1" "2" (concatenation)) null)
'(concatenation "1" "2" (concatenation)))
(check-equal? (parse #'(char-range "1" #\1) null) '(char-range #\1 #\1))
(check-equal? (parse #'(char-range #\1 "1") null) '(char-range #\1 #\1))
(check-equal? (parse #'(char-range "1" "3") null) '(char-range #\1 #\3))
(check-equal? (parse #'(char-complement (union "1" "2")) null)
'(char-complement (union "1" "2"))))
; )
;; yikes... these test cases all have the wrong arity, now.
;; and by "now", I mean it's been broken since before we
;; moved to git.
(module+ test
(check-equal? (parse #'#\a null) #\a)
(check-equal? (parse #'"1" null) "1")
(check-equal? (parse #'(repetition 1 1 #\1) null)
'(repetition 1 1 #\1))
(check-equal? (parse #'(repetition 0 +inf.0 #\1) null) '(repetition 0 +inf.0 #\1))
(check-equal? (parse #'(union #\1 (union "2") (union)) null)
'(union #\1 (union "2") (union)))
(check-equal? (parse #'(intersection #\1 (intersection "2") (intersection))
null)
'(intersection #\1 (intersection "2") (intersection)))
(check-equal? (parse #'(complement (union #\1 #\2))
null)
'(complement (union #\1 #\2)))
(check-equal? (parse #'(concatenation "1" "2" (concatenation)) null)
'(concatenation "1" "2" (concatenation)))
(check-equal? (parse #'(char-range "1" #\1) null) '(char-range #\1 #\1))
(check-equal? (parse #'(char-range #\1 "1") null) '(char-range #\1 #\1))
(check-equal? (parse #'(char-range "1" "3") null) '(char-range #\1 #\3))
(check-equal? (parse #'(char-complement (union "1" "2")) null)
'(char-complement (union "1" "2"))))

@ -1,9 +1,7 @@
(module token-syntax mzscheme
#lang racket/base
(provide make-terminals-def terminals-def-t terminals-def?
make-e-terminals-def e-terminals-def-t e-terminals-def?)
;; The things needed at compile time to handle definition of tokens
(provide make-terminals-def terminals-def-t terminals-def?
make-e-terminals-def e-terminals-def-t e-terminals-def?)
(define-struct terminals-def (t))
(define-struct e-terminals-def (t))
)
;; The things needed at compile time to handle definition of tokens
(define-struct terminals-def (t))
(define-struct e-terminals-def (t))

@ -1,92 +1,80 @@
(module token mzscheme
(require-for-syntax "token-syntax.rkt")
#lang racket/base
(require (for-syntax racket/base "token-syntax.rkt"))
;; Defining tokens
;; Defining tokens
(provide define-tokens define-empty-tokens make-token token?
(protect (rename token-name real-token-name))
(protect (rename token-value real-token-value))
(rename token-name* token-name)
(rename token-value* token-value)
(struct position (offset line col))
(struct position-token (token start-pos end-pos))
(struct srcloc-token (token srcloc)))
(provide define-tokens define-empty-tokens make-token token?
(protect-out (rename-out [token-name real-token-name]))
(protect-out (rename-out [token-value real-token-value]))
(rename-out [token-name* token-name][token-value* token-value])
(struct-out position)
(struct-out position-token)
(struct-out srcloc-token))
;; A token is either
;; - symbol
;; - (make-token symbol any)
(define-struct token (name value) (make-inspector))
;; A token is either
;; - symbol
;; - (make-token symbol any)
(define-struct token (name value) #:inspector (make-inspector))
;; token-name*: token -> symbol
(define (token-name* t)
(cond
((symbol? t) t)
((token? t) (token-name t))
(else (raise-type-error
'token-name
"symbol or struct:token"
0
t))))
;; token-name*: token -> symbol
(define (token-name* t)
(cond
[(symbol? t) t]
[(token? t) (token-name t)]
[else (raise-type-error 'token-name "symbol or struct:token" 0 t)]))
;; token-value*: token -> any
(define (token-value* t)
(cond
((symbol? t) #f)
((token? t) (token-value t))
(else (raise-type-error
'token-value
"symbol or struct:token"
0
t))))
;; token-value*: token -> any
(define (token-value* t)
(cond
[(symbol? t) #f]
[(token? t) (token-value t)]
[else (raise-type-error 'token-value "symbol or struct:token" 0 t)]))
(define-for-syntax (make-ctor-name n)
(datum->syntax-object n
(string->symbol (format "token-~a" (syntax-e n)))
n
n))
(define-for-syntax (make-ctor-name n)
(datum->syntax n
(string->symbol (format "token-~a" (syntax-e n)))
n
n))
(define-for-syntax (make-define-tokens empty?)
(lambda (stx)
(syntax-case stx ()
((_ name (token ...))
(andmap identifier? (syntax->list (syntax (token ...))))
(with-syntax (((marked-token ...)
(map values #;(make-syntax-introducer)
(syntax->list (syntax (token ...))))))
(quasisyntax/loc stx
(begin
(define-syntax name
#,(if empty?
#'(make-e-terminals-def (quote-syntax (marked-token ...)))
#'(make-terminals-def (quote-syntax (marked-token ...)))))
#,@(map
(lambda (n)
(when (eq? (syntax-e n) 'error)
(raise-syntax-error
#f
"Cannot define a token named error."
stx))
(if empty?
#`(define (#,(make-ctor-name n))
'#,n)
#`(define (#,(make-ctor-name n) x)
(make-token '#,n x))))
(syntax->list (syntax (token ...))))
#;(define marked-token #f) #;...))))
((_ ...)
(raise-syntax-error
#f
"must have the form (define-tokens name (identifier ...)) or (define-empty-tokens name (identifier ...))"
stx)))))
(define-for-syntax ((make-define-tokens empty?) stx)
(syntax-case stx ()
[(_ NAME (TOKEN ...))
(andmap identifier? (syntax->list #'(TOKEN ...)))
(with-syntax (((marked-token ...)
(map values #;(make-syntax-introducer)
(syntax->list #'(TOKEN ...)))))
(quasisyntax/loc stx
(begin
(define-syntax NAME
#,(if empty?
#'(make-e-terminals-def (quote-syntax (marked-token ...)))
#'(make-terminals-def (quote-syntax (marked-token ...)))))
#,@(map
(λ (n)
(when (eq? (syntax-e n) 'error)
(raise-syntax-error
#f
"Cannot define a token named error."
stx))
(if empty?
#`(define (#,(make-ctor-name n))
'#,n)
#`(define (#,(make-ctor-name n) x)
(make-token '#,n x))))
(syntax->list #'(TOKEN ...)))
#;(define marked-token #f) #;...)))]
[(_ ...)
(raise-syntax-error #f
"must have the form (define-tokens name (identifier ...)) or (define-empty-tokens name (identifier ...))"
stx)]))
(define-syntax define-tokens (make-define-tokens #f))
(define-syntax define-empty-tokens (make-define-tokens #t))
(define-syntax define-tokens (make-define-tokens #f))
(define-syntax define-empty-tokens (make-define-tokens #t))
(define-struct position (offset line col) #f)
(define-struct position-token (token start-pos end-pos) #f)
(define-struct position (offset line col) #:inspector #f)
(define-struct position-token (token start-pos end-pos) #:inspector #f)
(define-struct srcloc-token (token srcloc) #f)
)
(define-struct srcloc-token (token srcloc) #:inspector #f)

@ -1,6 +1,5 @@
#lang racket
(require "util.rkt")
#lang racket/base
(require racket/promise "util.rkt")
(provide (all-defined-out))
@ -10,36 +9,33 @@
;; get-chars-for-x : (nat -> bool) (listof (list nat nat bool)) -> (listof (cons nat nat))
(define (get-chars-for char-x? mapped-chars)
(cond
((null? mapped-chars) null)
(else
(let* ((range (car mapped-chars))
(low (car range))
(high (cadr range))
(x (char-x? low)))
(cond
((caddr range)
(if x
(cons (cons low high)
(get-chars-for char-x? (cdr mapped-chars)))
(get-chars-for char-x? (cdr mapped-chars))))
(else
(let loop ((range-start low)
(i (car range))
(parity x))
(cond
((> i high)
(if parity
(cons (cons range-start high) (get-chars-for char-x? (cdr mapped-chars)))
(get-chars-for char-x? (cdr mapped-chars))))
((eq? parity (char-x? i))
(loop range-start (add1 i) parity))
(parity
(cons (cons range-start (sub1 i)) (loop i (add1 i) #f)))
(else
(loop i (add1 i) #t))))))))))
[(null? mapped-chars) null]
[else
(define range (car mapped-chars))
(define low (car range))
(define high (cadr range))
(define x (char-x? low))
(cond
[(caddr range)
(if x
(cons (cons low high) (get-chars-for char-x? (cdr mapped-chars)))
(get-chars-for char-x? (cdr mapped-chars)))]
[else
(let loop ([range-start low]
[i (car range)]
[parity x])
(cond
[(> i high)
(if parity
(cons (cons range-start high) (get-chars-for char-x? (cdr mapped-chars)))
(get-chars-for char-x? (cdr mapped-chars)))]
[(eq? parity (char-x? i))
(loop range-start (add1 i) parity)]
[parity (cons (cons range-start (sub1 i)) (loop i (add1 i) #f))]
[else (loop i (add1 i) #t)]))])]))
(define (compute-ranges x?)
(delay (get-chars-for (lambda (x) (x? (integer->char x))) mapped-chars)))
(delay (get-chars-for (λ (x) (x? (integer->char x))) mapped-chars)))
(define alphabetic-ranges (compute-ranges char-alphabetic?)) ;; 325
(define lower-case-ranges (compute-ranges char-lower-case?)) ;; 405
@ -61,7 +57,7 @@
(check-equal? (get-chars-for odd? '()) '())
(check-equal? (get-chars-for odd? '((1 4 #f) (8 13 #f)))
'((1 . 1) (3 . 3) (9 . 9) (11 . 11) (13 . 13)))
(check-equal? (get-chars-for (lambda (x)
(check-equal? (get-chars-for (λ (x)
(odd? (quotient x 10)))
'((1 5 #t) (17 19 #t) (21 51 #f)))
'((17 . 19) (30 . 39) (50 . 51))))

@ -1,4 +1,5 @@
#lang racket
#lang racket/base
(require (for-syntax racket/base))
(provide (all-defined-out))
@ -10,18 +11,18 @@
(module+ test
(require rackunit))
(define-syntax (test-block stx)
(syntax-case stx ()
[(_ defs (code right-ans) ...)
#'(module+ test
(require rackunit)
(let* defs
(let ([real-ans code])
(check-equal? real-ans right-ans)) ...))]))
#;(define-syntax test-block
(syntax-rules ()
((_ defs (code right-ans) ...)
(let* defs
(let ((real-ans code))
(unless (equal? real-ans right-ans)
(printf "Test failed: ~e gave ~e. Expected ~e\n"
'code real-ans 'right-ans))) ...))))
(define-syntax test-block
(syntax-rules ()
((_ x ...) (void))))
((_ x ...) (void))))
;; A cache is (X ( -> Y) -> Y)
@ -31,23 +32,22 @@
;; returned.
;; Xs are compared with equal?
(define (make-cache)
(let ((table (make-hash)))
(lambda (key build)
(hash-ref table key
(lambda ()
(let ((new (build)))
(hash-set! table key new)
new))))))
(let ([table (make-hash)])
(λ (key build)
(hash-ref table key (λ ()
(let ([new (build)])
(hash-set! table key new)
new))))))
(module+ test
(define cache (make-cache))
(check-equal? (cache '(s 1 2) (lambda () 9)) 9)
(check-equal? (cache '(s 2 1) (lambda () 8)) 8)
(check-equal? (cache '(s 1 2) (lambda () 1)) 9)
(check-equal? (cache '(s 1 2) (λ () 9)) 9)
(check-equal? (cache '(s 2 1) (λ () 8)) 8)
(check-equal? (cache '(s 1 2) (λ () 1)) 9)
(check-equal? (cache (cons 's (cons 0 (cons +inf.0 10)))
(lambda () 22)) 22)
(λ () 22)) 22)
(check-equal? (cache (cons 's (cons 0 (cons +inf.0 10)))
(lambda () 1)) 22))
(λ () 1)) 22))
@ -55,8 +55,8 @@
;; makes a function that returns a higher number by 1, each time
;; it is called.
(define (make-counter)
(let ((counter 0))
(lambda ()
(let ([counter 0])
(λ ()
(begin0
counter
(set! counter (add1 counter))))))
@ -76,33 +76,33 @@
;; previous entry. l must be grouped by indexes.
(define (remove-dups l index acc)
(cond
((null? l) (reverse acc))
((null? acc) (remove-dups (cdr l) index (cons (car l) acc)))
((= (index (car acc)) (index (car l)))
(remove-dups (cdr l) index acc))
(else
(remove-dups (cdr l) index (cons (car l) acc)))))
[(null? l) (reverse acc)]
[(null? acc) (remove-dups (cdr l) index (cons (car l) acc))]
[(= (index (car acc)) (index (car l)))
(remove-dups (cdr l) index acc)]
[else
(remove-dups (cdr l) index (cons (car l) acc))]))
(module+ test
(check-equal? (remove-dups '((1 2) (2 2) (1 3) (1 4)
(100 4) (0 5)) cadr null)
'((1 2) (1 3) (1 4) (0 5)))
'((1 2) (1 3) (1 4) (0 5)))
(check-equal? (remove-dups null error null) null))
;; do-simple-equiv : (list-of X) (X -> nat) -> (list-of X)
;; Sorts l according to index and removes the entries with duplicate
;; indexes.
(define (do-simple-equiv l index)
(let ((ordered (sort l (lambda (a b) (< (index a) (index b))))))
(remove-dups ordered index null)))
(define ordered (sort l (λ (a b) (< (index a) (index b)))))
(remove-dups ordered index null))
(module+ test
(check-equal? (do-simple-equiv '((2 2) (1 4) (1 2)
(100 4) (1 3) (0 5))
cadr)
'((2 2) (1 3) (1 4) (0 5)))
(check-equal? (do-simple-equiv null error) null))
(check-equal? (do-simple-equiv '((2 2) (1 4) (1 2)
(100 4) (1 3) (0 5))
cadr)
'((2 2) (1 3) (1 4) (0 5)))
(check-equal? (do-simple-equiv null error) null))
;; replace : (list-of X) (X -> bool) (X -> (list-of X)) (list-of X) ->
;; (list-of X)
@ -110,16 +110,16 @@
;; list.
(define (replace l pred? get acc)
(cond
((null? l) acc)
((pred? (car l)) (replace (cdr l) pred? get (append (get (car l)) acc)))
(else (replace (cdr l) pred? get (cons (car l) acc)))))
[(null? l) acc]
[(pred? (car l)) (replace (cdr l) pred? get (append (get (car l)) acc))]
[else (replace (cdr l) pred? get (cons (car l) acc))]))
(module+ test
(check-equal? (replace null void (lambda () (list 1)) null) null)
(check-equal? (replace null void (λ () (list 1)) null) null)
(check-equal? (replace '(1 2 3 4 3 5)
(lambda (x) (= x 3))
(lambda (x) (list 1 2 3))
(λ (x) (= x 3))
(λ (x) (list 1 2 3))
null)
'(5 1 2 3 4 1 2 3 2 1)))

@ -1,280 +1,250 @@
#lang racket/base
;; Constructs to create and access grammars, the internal
;; representation of the input to the parser generator.
(module grammar mzscheme
(require mzlib/class
mzlib/list
"yacc-helper.rkt"
racket/contract)
(require racket/class
(except-in racket/list remove-duplicates)
"yacc-helper.rkt"
racket/contract)
;; Each production has a unique index 0 <= index <= number of productions
(define-struct prod (lhs rhs index prec action) (make-inspector))
;; Each production has a unique index 0 <= index <= number of productions
(define-struct prod (lhs rhs index prec action) #:inspector (make-inspector) #:mutable)
;; The dot-pos field is the index of the element in the rhs
;; of prod that the dot immediately precedes.
;; Thus 0 <= dot-pos <= (vector-length rhs).
(define-struct item (prod dot-pos) (make-inspector))
;; The dot-pos field is the index of the element in the rhs
;; of prod that the dot immediately precedes.
;; Thus 0 <= dot-pos <= (vector-length rhs).
(define-struct item (prod dot-pos) #:inspector (make-inspector))
;; gram-sym = (union term? non-term?)
;; Each term has a unique index 0 <= index < number of terms
;; Each non-term has a unique index 0 <= index < number of non-terms
(define-struct term (sym index prec) (make-inspector))
(define-struct non-term (sym index) (make-inspector))
;; a precedence declaration.
(define-struct prec (num assoc) (make-inspector))
;; gram-sym = (union term? non-term?)
;; Each term has a unique index 0 <= index < number of terms
;; Each non-term has a unique index 0 <= index < number of non-terms
(define-struct term (sym index prec) #:inspector (make-inspector) #:mutable)
(define-struct non-term (sym index) #:inspector (make-inspector) #:mutable)
;; a precedence declaration.
(define-struct prec (num assoc) #:inspector (make-inspector))
(provide/contract
(make-item (prod? (or/c #f natural-number/c) . -> . item?))
(make-term (symbol? (or/c #f natural-number/c) (or/c prec? #f) . -> . term?))
(make-non-term (symbol? (or/c #f natural-number/c) . -> . non-term?))
(make-prec (natural-number/c (or/c 'left 'right 'nonassoc) . -> . prec?))
(make-prod (non-term? (vectorof (or/c non-term? term?))
(or/c #f natural-number/c) (or/c #f prec?) syntax? . -> . prod?)))
(provide/contract
[make-item (prod? (or/c #f natural-number/c) . -> . item?)]
[make-term (symbol? (or/c #f natural-number/c) (or/c prec? #f) . -> . term?)]
[make-non-term (symbol? (or/c #f natural-number/c) . -> . non-term?)]
[make-prec (natural-number/c (or/c 'left 'right 'nonassoc) . -> . prec?)]
[make-prod (non-term? (vectorof (or/c non-term? term?))
(or/c #f natural-number/c) (or/c #f prec?) syntax? . -> . prod?)])
(provide
;; Things that work on items
start-item? item-prod item->string
sym-at-dot move-dot-right item<? item-dot-pos
(provide
;; Things that work on items
start-item? item-prod item->string
sym-at-dot move-dot-right item<? item-dot-pos
;; Things that operate on grammar symbols
gram-sym-symbol gram-sym-index term-prec gram-sym->string
non-term? term? non-term<? term<?
term-list->bit-vector term-index non-term-index
;; Things that operate on grammar symbols
gram-sym-symbol gram-sym-index term-prec gram-sym->string
non-term? term? non-term<? term<?
term-list->bit-vector term-index non-term-index
;; Things that work on precs
prec-num prec-assoc
;; Things that work on precs
prec-num prec-assoc
grammar%
grammar%
;; Things that work on productions
prod-index prod-prec prod-rhs prod-lhs prod-action)
;; Things that work on productions
prod-index prod-prec prod-rhs prod-lhs prod-action)
;;---------------------- LR items --------------------------
;;---------------------- LR items --------------------------
;; item<?: LR-item * LR-item -> bool
;; Lexicographic comparison on two items.
(define (item<? i1 i2)
(let ((p1 (prod-index (item-prod i1)))
(p2 (prod-index (item-prod i2))))
(or (< p1 p2)
(and (= p1 p2)
(let ((d1 (item-dot-pos i1))
(d2 (item-dot-pos i2)))
(< d1 d2))))))
;; start-item?: LR-item -> bool
;; The start production always has index 0
(define (start-item? i)
(= 0 (non-term-index (prod-lhs (item-prod i)))))
;; item<?: LR-item * LR-item -> bool
;; Lexicographic comparison on two items.
(define (item<? i1 i2)
(define p1 (prod-index (item-prod i1)))
(define p2 (prod-index (item-prod i2)))
(or (< p1 p2)
(and (= p1 p2)
(< (item-dot-pos i1) (item-dot-pos i2)))))
;; start-item?: LR-item -> bool
;; The start production always has index 0
(define (start-item? i)
(zero? (non-term-index (prod-lhs (item-prod i)))))
;; move-dot-right: LR-item -> LR-item | #f
;; moves the dot to the right in the item, unless it is at its
;; rightmost, then it returns false
(define (move-dot-right i)
(cond
((= (item-dot-pos i) (vector-length (prod-rhs (item-prod i)))) #f)
(else (make-item (item-prod i)
(add1 (item-dot-pos i))))))
;; sym-at-dot: LR-item -> gram-sym | #f
;; returns the symbol after the dot in the item or #f if there is none
(define (sym-at-dot i)
(let ((dp (item-dot-pos i))
(rhs (prod-rhs (item-prod i))))
(cond
((= dp (vector-length rhs)) #f)
(else (vector-ref rhs dp)))))
;; move-dot-right: LR-item -> LR-item | #f
;; moves the dot to the right in the item, unless it is at its
;; rightmost, then it returns false
(define (move-dot-right i)
(cond
[(= (item-dot-pos i) (vector-length (prod-rhs (item-prod i)))) #f]
[else (make-item (item-prod i)
(add1 (item-dot-pos i)))]))
;; sym-at-dot: LR-item -> gram-sym | #f
;; returns the symbol after the dot in the item or #f if there is none
(define (sym-at-dot i)
(define dp (item-dot-pos i))
(define rhs (prod-rhs (item-prod i)))
(cond
[(= dp (vector-length rhs)) #f]
[else (vector-ref rhs dp)]))
;; print-item: LR-item ->
(define (item->string it)
(let ((print-sym (lambda (i)
(let ((gs (vector-ref (prod-rhs (item-prod it)) i)))
(cond
((term? gs) (format "~a " (term-sym gs)))
(else (format "~a " (non-term-sym gs))))))))
(string-append
(format "~a -> " (non-term-sym (prod-lhs (item-prod it))))
(let loop ((i 0))
(cond
((= i (vector-length (prod-rhs (item-prod it))))
(if (= i (item-dot-pos it))
". "
""))
((= i (item-dot-pos it))
(string-append ". " (print-sym i) (loop (add1 i))))
(else (string-append (print-sym i) (loop (add1 i)))))))))
;; --------------------- Grammar Symbols --------------------------
(define (non-term<? nt1 nt2)
(< (non-term-index nt1) (non-term-index nt2)))
;; print-item: LR-item ->
(define (item->string it)
(define print-sym (λ (i)
(let ((gs (vector-ref (prod-rhs (item-prod it)) i)))
(cond
((term? gs) (format "~a " (term-sym gs)))
(else (format "~a " (non-term-sym gs)))))))
(string-append
(format "~a -> " (non-term-sym (prod-lhs (item-prod it))))
(let loop ((i 0))
(cond
[(= i (vector-length (prod-rhs (item-prod it))))
(if (= i (item-dot-pos it))
". "
"")]
[(= i (item-dot-pos it))
(string-append ". " (print-sym i) (loop (add1 i)))]
[else (string-append (print-sym i) (loop (add1 i)))]))))
;; --------------------- Grammar Symbols --------------------------
(define (non-term<? nt1 nt2)
(< (non-term-index nt1) (non-term-index nt2)))
(define (term<? nt1 nt2)
(< (term-index nt1) (term-index nt2)))
(define (gram-sym-index gs)
(if (term? gs)
(term-index gs)
(non-term-index gs)))
(define (gram-sym-symbol gs)
(if (term? gs)
(term-sym gs)
(non-term-sym gs)))
(define (gram-sym->string gs)
(symbol->string (gram-sym-symbol gs)))
;; term-list->bit-vector: term list -> int
;; Creates a number where the nth bit is 1 if the term with index n is in
;; the list, and whose nth bit is 0 otherwise
(define (term-list->bit-vector terms)
(if (null? terms)
0
(bitwise-ior (arithmetic-shift 1 (term-index (car terms)))
(term-list->bit-vector (cdr terms)))))
(define (term<? nt1 nt2)
(< (term-index nt1) (term-index nt2)))
(define (gram-sym-index gs)
(cond
((term? gs) (term-index gs))
(else (non-term-index gs))))
(define (gram-sym-symbol gs)
(cond
((term? gs) (term-sym gs))
(else (non-term-sym gs))))
(define (gram-sym->string gs)
(symbol->string (gram-sym-symbol gs)))
;; term-list->bit-vector: term list -> int
;; Creates a number where the nth bit is 1 if the term with index n is in
;; the list, and whose nth bit is 0 otherwise
(define (term-list->bit-vector terms)
(cond
((null? terms) 0)
(else
(bitwise-ior (arithmetic-shift 1 (term-index (car terms))) (term-list->bit-vector (cdr terms))))))
;; ------------------------- Grammar ------------------------------
(define grammar%
(class object%
(super-instantiate ())
;; prods: production list list
;; where there is one production list per non-term
(init prods)
;; init-prods: production list
;; The productions parsing can start from
;; nullable-non-terms is indexed by the non-term-index and is true iff non-term is nullable
(init-field init-prods terms non-terms end-terms)
;; list of all productions
(define all-prods (apply append prods))
(define num-prods (length all-prods))
(define num-terms (length terms))
(define num-non-terms (length non-terms))
;; ------------------------- Grammar ------------------------------
(for ([(nt count) (in-indexed non-terms)])
(set-non-term-index! nt count))
(define grammar%
(class object%
(super-instantiate ())
;; prods: production list list
;; where there is one production list per non-term
(init prods)
;; init-prods: production list
;; The productions parsing can start from
;; nullable-non-terms is indexed by the non-term-index and is true iff non-term is nullable
(init-field init-prods terms non-terms end-terms)
;; list of all productions
(define all-prods (apply append prods))
(define num-prods (length all-prods))
(define num-terms (length terms))
(define num-non-terms (length non-terms))
(let ((count 0))
(for-each
(lambda (nt)
(set-non-term-index! nt count)
(set! count (add1 count)))
non-terms))
(let ((count 0))
(for-each
(lambda (t)
(set-term-index! t count)
(set! count (add1 count)))
terms))
(for ([(t count) (in-indexed terms)])
(set-term-index! t count))
(let ((count 0))
(for-each
(lambda (prod)
(set-prod-index! prod count)
(set! count (add1 count)))
all-prods))
(for ([(prod count) (in-indexed all-prods)])
(set-prod-index! prod count))
;; indexed by the index of the non-term - contains the list of productions for that non-term
(define nt->prods
(let ((v (make-vector (length prods) #f)))
(for-each (lambda (prods)
(vector-set! v (non-term-index (prod-lhs (car prods))) prods))
prods)
v))
;; indexed by the index of the non-term - contains the list of productions for that non-term
(define nt->prods
(let ((v (make-vector (length prods) #f)))
(for ([prods (in-list prods)])
(vector-set! v (non-term-index (prod-lhs (car prods))) prods))
v))
(define nullable-non-terms
(nullable all-prods num-non-terms))
(define nullable-non-terms
(nullable all-prods num-non-terms))
(define/public (get-num-terms) num-terms)
(define/public (get-num-non-terms) num-non-terms)
(define/public (get-num-terms) num-terms)
(define/public (get-num-non-terms) num-non-terms)
(define/public (get-prods-for-non-term nt)
(vector-ref nt->prods (non-term-index nt)))
(define/public (get-prods) all-prods)
(define/public (get-init-prods) init-prods)
(define/public (get-prods-for-non-term nt)
(vector-ref nt->prods (non-term-index nt)))
(define/public (get-prods) all-prods)
(define/public (get-init-prods) init-prods)
(define/public (get-terms) terms)
(define/public (get-non-terms) non-terms)
(define/public (get-terms) terms)
(define/public (get-non-terms) non-terms)
(define/public (get-num-prods) num-prods)
(define/public (get-end-terms) end-terms)
(define/public (get-num-prods) num-prods)
(define/public (get-end-terms) end-terms)
(define/public (nullable-non-term? nt)
(vector-ref nullable-non-terms (non-term-index nt)))
(define/public (nullable-after-dot? item)
(let* ((rhs (prod-rhs (item-prod item)))
(prod-length (vector-length rhs)))
(let loop ((i (item-dot-pos item)))
(cond
((< i prod-length)
(if (and (non-term? (vector-ref rhs i)) (nullable-non-term? (vector-ref rhs i)))
(loop (add1 i))
#f))
((= i prod-length) #t)))))
(define/public (nullable-non-term? nt)
(vector-ref nullable-non-terms (non-term-index nt)))
(define/public (nullable-after-dot? item)
(define rhs (prod-rhs (item-prod item)))
(define prod-length (vector-length rhs))
(let loop ((i (item-dot-pos item)))
(cond
[(< i prod-length)
(and (non-term? (vector-ref rhs i))
(nullable-non-term? (vector-ref rhs i))
(loop (add1 i)))]
[(= i prod-length)])))
(define/public (nullable-non-term-thunk)
(lambda (nt)
(nullable-non-term? nt)))
(define/public (nullable-after-dot?-thunk)
(lambda (item)
(nullable-after-dot? item)))))
(define/public (nullable-non-term-thunk)
(λ (nt) (nullable-non-term? nt)))
(define/public (nullable-after-dot?-thunk)
(λ (item) (nullable-after-dot? item)))))
;; nullable: production list * int -> non-term set
;; determines which non-terminals can derive epsilon
(define (nullable prods num-nts)
(letrec ((nullable (make-vector num-nts #f))
(added #f)
;; nullable: production list * int -> non-term set
;; determines which non-terminals can derive epsilon
(define (nullable prods num-nts)
(define nullable (make-vector num-nts #f))
(define added #f)
;; possible-nullable: producion list -> production list
;; Removes all productions that have a terminal
(possible-nullable
(lambda (prods)
(filter (lambda (prod)
(vector-andmap non-term? (prod-rhs prod)))
prods)))
;; possible-nullable: producion list -> production list
;; Removes all productions that have a terminal
(define (possible-nullable prods)
(for/list ([prod (in-list prods)]
#:when (vector-andmap non-term? (prod-rhs prod)))
prod))
;; set-nullables: production list -> production list
;; makes one pass through the productions, adding the ones
;; known to be nullable now to nullable and returning a list
;; of productions that we don't know about yet.
(set-nullables
(lambda (prods)
(cond
((null? prods) null)
((vector-ref nullable
(gram-sym-index (prod-lhs (car prods))))
(set-nullables (cdr prods)))
((vector-andmap (lambda (nt)
(vector-ref nullable (gram-sym-index nt)))
(prod-rhs (car prods)))
(vector-set! nullable
(gram-sym-index (prod-lhs (car prods)))
#t)
(set! added #t)
(set-nullables (cdr prods)))
(else
(cons (car prods)
(set-nullables (cdr prods))))))))
(let loop ((P (possible-nullable prods)))
(cond
((null? P) nullable)
(else
(set! added #f)
(let ((new-P (set-nullables P)))
(if added
(loop new-P)
nullable)))))))
;; set-nullables: production list -> production list
;; makes one pass through the productions, adding the ones
;; known to be nullable now to nullable and returning a list
;; of productions that we don't know about yet.
(define (set-nullables prods)
(cond
[(null? prods) null]
[(vector-ref nullable (gram-sym-index (prod-lhs (car prods))))
(set-nullables (cdr prods))]
[(vector-andmap (λ (nt) (vector-ref nullable (gram-sym-index nt))) (prod-rhs (car prods)))
(vector-set! nullable (gram-sym-index (prod-lhs (car prods))) #t)
(set! added #t)
(set-nullables (cdr prods))]
[else (cons (car prods) (set-nullables (cdr prods)))]))
(let loop ((P (possible-nullable prods)))
(cond
[(null? P) nullable]
[else
(set! added #f)
(define new-P (set-nullables P))
(if added
(loop new-P)
nullable)])))
)

@ -1,61 +1,53 @@
(module graph mzscheme
#lang racket/base
(provide digraph)
(provide digraph)
(define (zero-thunk) 0)
(define (zero-thunk) 0)
;; digraph:
;; ('a list) * ('a -> 'a list) * ('a -> 'b) * ('b * 'b -> 'b) * (-> 'b)
;; -> ('a -> 'b)
;; DeRemer and Pennello 1982
;; Computes (f x) = (f- x) union Union{(f y) | y in (edges x)}
;; We use a hash-table to represent the result function 'a -> 'b set, so
;; the values of type 'a must be comparable with eq?.
(define (digraph nodes edges f- union fail)
(letrec [
;; Will map elements of 'a to 'b sets
(results (make-hash-table))
(f (lambda (x) (hash-table-get results x fail)))
;; Maps elements of 'a to integers.
(N (make-hash-table))
(get-N (lambda (x) (hash-table-get N x zero-thunk)))
(set-N (lambda (x d) (hash-table-put! N x d)))
(stack null)
(push (lambda (x)
(set! stack (cons x stack))))
(pop (lambda ()
(begin0
(car stack)
(set! stack (cdr stack)))))
(depth (lambda () (length stack)))
;; digraph:
;; ('a list) * ('a -> 'a list) * ('a -> 'b) * ('b * 'b -> 'b) * (-> 'b)
;; -> ('a -> 'b)
;; DeRemer and Pennello 1982
;; Computes (f x) = (f- x) union Union{(f y) | y in (edges x)}
;; We use a hash-table to represent the result function 'a -> 'b set, so
;; the values of type 'a must be comparable with eq?.
(define (digraph nodes edges f- union fail)
(define results (make-hasheq))
(define (f x) (hash-ref results x fail))
;; Maps elements of 'a to integers.
(define N (make-hasheq))
(define (get-N x) (hash-ref N x zero-thunk))
(define (set-N x d) (hash-set! N x d))
(define stack null)
(define (push x) (set! stack (cons x stack)))
(define (pop) (begin0
(car stack)
(set! stack (cdr stack))))
(define (depth) (length stack))
;; traverse: 'a ->
(traverse
(lambda (x)
(push x)
(let ((d (depth)))
(set-N x d)
(hash-table-put! results x (f- x))
(for-each (lambda (y)
(if (= 0 (get-N y))
(traverse y))
(hash-table-put! results
x
(union (f x) (f y)))
(set-N x (min (get-N x) (get-N y))))
(edges x))
(if (= d (get-N x))
(let loop ((p (pop)))
(set-N p +inf.0)
(hash-table-put! results p (f x))
(if (not (eq? x p))
(loop (pop))))))))]
(for-each (lambda (x)
(if (= 0 (get-N x))
(traverse x)))
nodes)
f))
;; traverse: 'a ->
(define (traverse x)
(push x)
(define d (depth))
(set-N x d)
(hash-set! results x (f- x))
(for-each (λ (y)
(when (= 0 (get-N y))
(traverse y))
(hash-set! results
x
(union (f x) (f y)))
(set-N x (min (get-N x) (get-N y))))
(edges x))
(when (= d (get-N x))
(let loop ([p (pop)])
(set-N p +inf.0)
(hash-set! results p (f x))
(when (not (eq? x p))
(loop (pop))))))
;; Will map elements of 'a to 'b sets
(for ([x (in-list nodes)]
#:when (zero? (get-N x)))
(traverse x))
f)
)

@ -1,374 +1,297 @@
(module input-file-parser mzscheme
#lang racket/base
(require "yacc-helper.rkt"
"../private-lex/token-syntax.rkt"
"grammar.rkt"
racket/class
racket/contract
(for-template racket/base))
;; routines for parsing the input to the parser generator and producing a
;; grammar (See grammar.rkt)
;; routines for parsing the input to the parser generator and producing a
;; grammar (See grammar.rkt)
(require "yacc-helper.rkt"
"../private-lex/token-syntax.rkt"
"grammar.rkt"
mzlib/class
racket/contract)
(require-for-template mzscheme)
(define (is-a-grammar%? x) (is-a? x grammar%))
(provide/contract
(parse-input ((listof identifier?) (listof identifier?) (listof identifier?)
(or/c #f syntax?) syntax? any/c . -> . is-a-grammar%?))
(get-term-list ((listof identifier?) . -> . (listof identifier?))))
(provide/contract
[parse-input ((listof identifier?) (listof identifier?) (listof identifier?)
(or/c #f syntax?) syntax? any/c . -> . is-a-grammar%?)]
[get-term-list ((listof identifier?) . -> . (listof identifier?))])
(define stx-for-original-property (read-syntax #f (open-input-string "original")))
(define stx-for-original-property (read-syntax #f (open-input-string "original")))
;; get-args: ??? -> (values (listof syntax) (or/c #f (cons integer? stx)))
(define (get-args i rhs src-pos term-defs)
(let ((empty-table (make-hash-table))
(biggest-pos #f))
(hash-table-put! empty-table 'error #t)
(for-each (lambda (td)
(let ((v (syntax-local-value td)))
(if (e-terminals-def? v)
(for-each (lambda (s)
(hash-table-put! empty-table (syntax-object->datum s) #t))
(syntax->list (e-terminals-def-t v))))))
term-defs)
(let ([args
(let get-args ((i i)
(rhs rhs))
(cond
((null? rhs) null)
(else
(let ((b (car rhs))
(name (if (hash-table-get empty-table (syntax-object->datum (car rhs)) (lambda () #f))
(gensym)
(string->symbol (format "$~a" i)))))
(cond
(src-pos
(let ([start-pos-id
(datum->syntax-object b (string->symbol (format "$~a-start-pos" i)) b stx-for-original-property)]
[end-pos-id
(datum->syntax-object b (string->symbol (format "$~a-end-pos" i)) b stx-for-original-property)])
(set! biggest-pos (cons start-pos-id end-pos-id))
`(,(datum->syntax-object b name b stx-for-original-property)
,start-pos-id
,end-pos-id
,@(get-args (add1 i) (cdr rhs)))))
(else
`(,(datum->syntax-object b name b stx-for-original-property)
,@(get-args (add1 i) (cdr rhs)))))))))])
(values args biggest-pos))))
;; get-args: ??? -> (values (listof syntax) (or/c #f (cons integer? stx)))
(define (get-args i rhs src-pos term-defs)
(define empty-table (make-hasheq))
(define biggest-pos #f)
(hash-set! empty-table 'error #t)
(for* ([td (in-list term-defs)]
[v (in-value (syntax-local-value td))]
#:when (e-terminals-def? v)
[s (in-list (syntax->list (e-terminals-def-t v)))])
(hash-set! empty-table (syntax->datum s) #t))
(define args
(let get-args ([i i][rhs rhs])
(cond
[(null? rhs) null]
[else
(define b (car rhs))
(define name (if (hash-ref empty-table (syntax->datum (car rhs)) #f)
(gensym)
(string->symbol (format "$~a" i))))
(cond
[src-pos
(define start-pos-id
(datum->syntax b (string->symbol (format "$~a-start-pos" i)) b stx-for-original-property))
(define end-pos-id
(datum->syntax b (string->symbol (format "$~a-end-pos" i)) b stx-for-original-property))
(set! biggest-pos (cons start-pos-id end-pos-id))
(list* (datum->syntax b name b stx-for-original-property)
start-pos-id
end-pos-id
(get-args (add1 i) (cdr rhs)))]
[else
(list* (datum->syntax b name b stx-for-original-property)
(get-args (add1 i) (cdr rhs)))])])))
(values args biggest-pos))
;; Given the list of terminal symbols and the precedence/associativity definitions,
;; builds terminal structures (See grammar.rkt)
;; build-terms: symbol list * symbol list list -> term list
(define (build-terms term-list precs)
(let ((counter 0)
;;(term-list (cons (gensym) term-list))
;; Will map a terminal symbol to its precedence/associativity
(prec-table (make-hash-table)))
;; Fill the prec table
(for-each
(lambda (p-decl)
(begin0
(let ((assoc (car p-decl)))
(for-each
(lambda (term-sym)
(hash-table-put! prec-table term-sym (make-prec counter assoc)))
(cdr p-decl)))
(set! counter (add1 counter))))
precs)
;; Given the list of terminal symbols and the precedence/associativity definitions,
;; builds terminal structures (See grammar.rkt)
;; build-terms: symbol list * symbol list list -> term list
(define (build-terms term-list precs)
(define counter 0)
;;(term-list (cons (gensym) term-list))
;; Will map a terminal symbol to its precedence/associativity
(define prec-table (make-hasheq))
;; Fill the prec table
(for ([p-decl (in-list precs)])
(define assoc (car p-decl))
(for ([term-sym (in-list (cdr p-decl))])
(hash-set! prec-table term-sym (make-prec counter assoc)))
(set! counter (add1 counter)))
;; Build the terminal structures
(map
(lambda (term-sym)
(make-term term-sym
#f
(hash-table-get prec-table term-sym (lambda () #f))))
term-list)))
;; Build the terminal structures
(for/list ([term-sym (in-list term-list)])
(make-term term-sym
#f
(hash-ref prec-table term-sym (λ () #f)))))
;; Retrieves the terminal symbols from a terminals-def (See terminal-syntax.rkt)
;; get-terms-from-def: identifier? -> (listof identifier?)
(define (get-terms-from-def term-syn)
(let ((t (syntax-local-value term-syn (lambda () #f))))
(cond
((terminals-def? t) (syntax->list (terminals-def-t t)))
((e-terminals-def? t) (syntax->list (e-terminals-def-t t)))
(else
(raise-syntax-error
'parser-tokens
"undefined token group"
term-syn)))))
;; Retrieves the terminal symbols from a terminals-def (See terminal-syntax.rkt)
;; get-terms-from-def: identifier? -> (listof identifier?)
(define (get-terms-from-def term-syn)
(define t (syntax-local-value term-syn #f))
(cond
[(terminals-def? t) (syntax->list (terminals-def-t t))]
[(e-terminals-def? t) (syntax->list (e-terminals-def-t t))]
[else
(raise-syntax-error
'parser-tokens
"undefined token group"
term-syn)]))
(define (get-term-list term-group-names)
(remove-duplicates
(cons (datum->syntax-object #f 'error)
(apply append
(map get-terms-from-def term-group-names)))))
(define (get-term-list term-group-names)
(remove-duplicates
(cons (datum->syntax #f 'error)
(apply append (map get-terms-from-def term-group-names)))))
(define (parse-input term-defs start ends prec-decls prods src-pos)
(let* ((start-syms (map syntax-e start))
(list-of-terms (map syntax-e (get-term-list term-defs)))
(end-terms
(map
(lambda (end)
(unless (memq (syntax-e end) list-of-terms)
(raise-syntax-error
'parser-end-tokens
(format "End token ~a not defined as a token"
(syntax-e end))
end))
(syntax-e end))
ends))
;; Get the list of terminals out of input-terms
(list-of-non-terms
(syntax-case prods ()
(((non-term production ...) ...)
(begin
(for-each
(lambda (nts)
(if (memq (syntax-object->datum nts) list-of-terms)
(raise-syntax-error
'parser-non-terminals
(format "~a used as both token and non-terminal"
(syntax-object->datum nts))
nts)))
(syntax->list (syntax (non-term ...))))
(let ((dup (duplicate-list? (syntax-object->datum
(syntax (non-term ...))))))
(if dup
(raise-syntax-error
'parser-non-terminals
(format "non-terminal ~a defined multiple times"
dup)
prods)))
(syntax-object->datum (syntax (non-term ...)))))
(_
(raise-syntax-error
'parser-grammar
"Grammar must be of the form (grammar (non-terminal productions ...) ...)"
prods))))
;; Check the precedence declarations for errors and turn them into data
(precs
(syntax-case prec-decls ()
(((type term ...) ...)
(let ((p-terms
(syntax-object->datum (syntax (term ... ...)))))
(cond
((duplicate-list? p-terms) =>
(lambda (d)
(define (parse-input term-defs start ends prec-decls prods src-pos)
(define start-syms (map syntax-e start))
(define list-of-terms (map syntax-e (get-term-list term-defs)))
(define end-terms
(for/list ([end (in-list ends)])
(unless (memq (syntax-e end) list-of-terms)
(raise-syntax-error
'parser-end-tokens
(format "End token ~a not defined as a token"
(syntax-e end))
end))
(syntax-e end)))
;; Get the list of terminals out of input-terms
(define list-of-non-terms
(syntax-case prods ()
[((NON-TERM PRODUCTION ...) ...)
(begin
(for ([nts (in-list (syntax->list #'(NON-TERM ...)))]
#:when (memq (syntax->datum nts) list-of-terms))
(raise-syntax-error
'parser-non-terminals
(format "~a used as both token and non-terminal" (syntax->datum nts))
nts))
(let ([dup (duplicate-list? (syntax->datum #'(NON-TERM ...)))])
(when dup
(raise-syntax-error
'parser-non-terminals
(format "non-terminal ~a defined multiple times" dup)
prods)))
(syntax->datum #'(NON-TERM ...)))]
[_ (raise-syntax-error
'parser-grammar
"Grammar must be of the form (grammar (non-terminal productions ...) ...)"
prods)]))
;; Check the precedence declarations for errors and turn them into data
(define precs
(syntax-case prec-decls ()
[((TYPE TERM ...) ...)
(let ([p-terms (syntax->datum #'(TERM ... ...))])
(cond
[(duplicate-list? p-terms) =>
(λ (d)
(raise-syntax-error
'parser-precedences
(format "duplicate precedence declaration for token ~a" d)
prec-decls))]
[else (for ([t (in-list (syntax->list #'(TERM ... ...)))]
#:when (not (memq (syntax->datum t) list-of-terms)))
(raise-syntax-error
'parser-precedences
(format "duplicate precedence declaration for token ~a"
d)
prec-decls)))
(else
(for-each
(lambda (a)
(for-each
(lambda (t)
(if (not (memq (syntax-object->datum t)
list-of-terms))
(raise-syntax-error
'parser-precedences
(format
"Precedence declared for non-token ~a"
(syntax-object->datum t))
t)))
(syntax->list a)))
(syntax->list (syntax ((term ...) ...))))
(for-each
(lambda (type)
(if (not (memq (syntax-object->datum type)
`(left right nonassoc)))
(raise-syntax-error
'parser-precedences
"Associativity must be left, right or nonassoc"
type)))
(syntax->list (syntax (type ...))))
(syntax-object->datum prec-decls)))))
(#f null)
(_
(raise-syntax-error
'parser-precedences
"Precedence declaration must be of the form (precs (assoc term ...) ...) where assoc is left, right or nonassoc"
prec-decls))))
(terms (build-terms list-of-terms precs))
(non-terms (map (lambda (non-term) (make-non-term non-term #f))
list-of-non-terms))
(term-table (make-hash-table))
(non-term-table (make-hash-table)))
(for-each (lambda (t)
(hash-table-put! term-table (gram-sym-symbol t) t))
terms)
(for-each (lambda (nt)
(hash-table-put! non-term-table (gram-sym-symbol nt) nt))
non-terms)
(let* (
;; parse-prod: syntax-object -> gram-sym vector
(parse-prod
(lambda (prod-so)
(syntax-case prod-so ()
((prod-rhs-sym ...)
(andmap identifier? (syntax->list prod-so))
(begin
(for-each (lambda (t)
(if (memq (syntax-object->datum t) end-terms)
(raise-syntax-error
'parser-production-rhs
(format "~a is an end token and cannot be used in a production"
(syntax-object->datum t))
t)))
(syntax->list prod-so))
(list->vector
(map (lambda (s)
(hash-table-get
term-table
(syntax-object->datum s)
(lambda ()
(hash-table-get
non-term-table
(syntax-object->datum s)
(lambda ()
(raise-syntax-error
'parser-production-rhs
(format
"~a is not declared as a terminal or non-terminal"
(syntax-object->datum s))
s))))))
(syntax->list prod-so)))))
(_
(raise-syntax-error
'parser-production-rhs
"production right-hand-side must have form (symbol ...)"
prod-so)))))
;; parse-action: syntax-object * syntax-object -> syntax-object
(parse-action
(lambda (rhs act)
(let-values ([(args biggest) (get-args 1 (syntax->list rhs) src-pos term-defs)])
(let ([act
(if biggest
(with-syntax ([$n-start-pos (datum->syntax-object (car biggest) '$n-start-pos)]
[$n-end-pos (datum->syntax-object (cdr biggest) '$n-end-pos)])
#`(let ([$n-start-pos #,(car biggest)]
[$n-end-pos #,(cdr biggest)])
#,act))
act)])
(quasisyntax/loc act
(lambda #,args
#,act))))))
;; parse-prod+action: non-term * syntax-object -> production
(parse-prod+action
(lambda (nt prod-so)
(syntax-case prod-so ()
((prod-rhs action)
(let ((p (parse-prod (syntax prod-rhs))))
(make-prod
nt
p
#f
(let loop ((i (sub1 (vector-length p))))
(if (>= i 0)
(let ((gs (vector-ref p i)))
(if (term? gs)
(term-prec gs)
(loop (sub1 i))))
#f))
(parse-action (syntax prod-rhs) (syntax action)))))
((prod-rhs (prec term) action)
(identifier? (syntax term))
(let ((p (parse-prod (syntax prod-rhs))))
(make-prod
nt
p
#f
(term-prec
(hash-table-get
term-table
(syntax-object->datum (syntax term))
(lambda ()
(raise-syntax-error
'parser-production-rhs
(format
"unrecognized terminal ~a in precedence declaration"
(syntax-object->datum (syntax term)))
(syntax term)))))
(parse-action (syntax prod-rhs) (syntax action)))))
(_
(raise-syntax-error
(format "Precedence declared for non-token ~a" (syntax->datum t))
t))
(for ([type (in-list (syntax->list #'(TYPE ...)))]
#:unless (memq (syntax->datum type) `(left right nonassoc)))
(raise-syntax-error
'parser-precedences
"Associativity must be left, right or nonassoc"
type))
(syntax->datum prec-decls)]))]
[#f null]
[_ (raise-syntax-error
'parser-precedences
"Precedence declaration must be of the form (precs (assoc term ...) ...) where assoc is left, right or nonassoc"
prec-decls)]))
(define terms (build-terms list-of-terms precs))
(define non-terms (map (λ (non-term) (make-non-term non-term #f))
list-of-non-terms))
(define term-table (make-hasheq))
(define non-term-table (make-hasheq))
(for ([t (in-list terms)])
(hash-set! term-table (gram-sym-symbol t) t))
(for ([nt (in-list non-terms)])
(hash-set! non-term-table (gram-sym-symbol nt) nt))
;; parse-prod: syntax-object -> gram-sym vector
(define (parse-prod prod-so)
(syntax-case prod-so ()
[(PROD-RHS-SYM ...)
(andmap identifier? (syntax->list prod-so))
(begin
(for ([t (in-list (syntax->list prod-so))]
#:when (memq (syntax->datum t) end-terms))
(raise-syntax-error
'parser-production-rhs
(format "~a is an end token and cannot be used in a production" (syntax->datum t))
t))
(for/vector ([s (in-list (syntax->list prod-so))])
(cond
[(hash-ref term-table (syntax->datum s) #f)]
[(hash-ref non-term-table (syntax->datum s) #f)]
[else (raise-syntax-error
'parser-production-rhs
(format "~a is not declared as a terminal or non-terminal" (syntax->datum s))
s)])))]
[_ (raise-syntax-error
'parser-production-rhs
"production right-hand-side must have form (symbol ...)"
prod-so)]))
;; parse-action: syntax-object * syntax-object -> syntax-object
(define (parse-action rhs act-in)
(define-values (args biggest) (get-args 1 (syntax->list rhs) src-pos term-defs))
(define act
(if biggest
(with-syntax ([(CAR-BIGGEST . CDR-BIGGEST) biggest]
[$N-START-POS (datum->syntax (car biggest) '$n-start-pos)]
[$N-END-POS (datum->syntax (cdr biggest) '$n-end-pos)]
[ACT-IN act-in])
#'(let ([$N-START-POS CAR-BIGGEST]
[$N-END-POS CDR-BIGGEST])
ACT-IN))
act-in))
(with-syntax ([ARGS args][ACT act])
(syntax/loc #'ACT (λ ARGS ACT))))
;; parse-prod+action: non-term * syntax-object -> production
(define (parse-prod+action nt prod-so)
(syntax-case prod-so ()
[(PROD-RHS ACTION)
(let ([p (parse-prod #'PROD-RHS)])
(make-prod
nt
p
#f
(let loop ([i (sub1 (vector-length p))])
(if (>= i 0)
(let ([gs (vector-ref p i)])
(if (term? gs)
(term-prec gs)
(loop (sub1 i))))
#f))
(parse-action #'PROD-RHS #'ACTION)))]
[(PROD-RHS (PREC TERM) ACTION)
(identifier? #'TERM)
(let ([p (parse-prod #'PROD-RHS)])
(make-prod
nt
p
#f
(term-prec
(cond
[(hash-ref term-table (syntax->datum #'TERM) #f)]
[else (raise-syntax-error
'parser-production-rhs
"production must have form [(symbol ...) expression] or [(symbol ...) (prec symbol) expression]"
prod-so)))))
;; parse-prod-for-nt: syntax-object -> production list
(parse-prods-for-nt
(lambda (prods-so)
(syntax-case prods-so ()
((nt productions ...)
(> (length (syntax->list (syntax (productions ...)))) 0)
(let ((nt (hash-table-get non-term-table
(syntax-object->datum (syntax nt)))))
(map (lambda (p) (parse-prod+action nt p))
(syntax->list (syntax (productions ...))))))
(_
(raise-syntax-error
'parser-productions
"A production for a non-terminal must be (non-term right-hand-side ...) with at least 1 right hand side"
prods-so))))))
(for-each
(lambda (sstx ssym)
(unless (memq ssym list-of-non-terms)
(raise-syntax-error
'parser-start
(format "Start symbol ~a not defined as a non-terminal" ssym)
sstx)))
start start-syms)
(let* ((starts (map (lambda (x) (make-non-term (gensym) #f)) start-syms))
(end-non-terms (map (lambda (x) (make-non-term (gensym) #f)) start-syms))
(parsed-prods (map parse-prods-for-nt (syntax->list prods)))
(start-prods
(map (lambda (start end-non-term)
(list (make-prod start (vector end-non-term) #f #f
(syntax (lambda (x) x)))))
starts end-non-terms))
(prods
`(,@start-prods
,@(map
(lambda (end-nt start-sym)
(map
(lambda (end)
(make-prod end-nt
(vector
(hash-table-get non-term-table start-sym)
(hash-table-get term-table end))
#f
#f
(syntax (lambda (x) x))))
end-terms))
end-non-terms start-syms)
,@parsed-prods)))
(format
"unrecognized terminal ~a in precedence declaration"
(syntax->datum #'TERM))
#'TERM)]))
(parse-action #'PROD-RHS #'ACTION)))]
[_ (raise-syntax-error
'parser-production-rhs
"production must have form [(symbol ...) expression] or [(symbol ...) (prec symbol) expression]"
prod-so)]))
;; parse-prod-for-nt: syntax-object -> production list
(define (parse-prods-for-nt prods-so)
(syntax-case prods-so ()
[(NT PRODUCTIONS ...)
(positive? (length (syntax->list #'(PRODUCTIONS ...))))
(let ([nt (hash-ref non-term-table (syntax->datum #'NT))])
(map (λ (p) (parse-prod+action nt p)) (syntax->list #'(PRODUCTIONS ...))))]
[_ (raise-syntax-error
'parser-productions
"A production for a non-terminal must be (non-term right-hand-side ...) with at least 1 right hand side"
prods-so)]))
(for ([sstx (in-list start)]
[ssym (in-list start-syms)]
#:unless (memq ssym list-of-non-terms))
(raise-syntax-error
'parser-start
(format "Start symbol ~a not defined as a non-terminal" ssym)
sstx))
(define starts (map (λ (x) (make-non-term (gensym) #f)) start-syms))
(define end-non-terms (map (λ (x) (make-non-term (gensym) #f)) start-syms))
(define parsed-prods (map parse-prods-for-nt (syntax->list prods)))
(define start-prods (for/list ([start (in-list starts)]
[end-non-term (in-list end-non-terms)])
(list (make-prod start (vector end-non-term) #f #f #'values))))
(define new-prods
(append start-prods
(for/list ([end-nt (in-list end-non-terms)]
[start-sym (in-list start-syms)])
(for/list ([end (in-list end-terms)])
(make-prod end-nt
(vector
(hash-ref non-term-table start-sym)
(hash-ref term-table end))
#f
#f
#'values)))
parsed-prods))
(make-object grammar%
prods
(map car start-prods)
terms
(append starts (append end-non-terms non-terms))
(map (lambda (term-name)
(hash-table-get term-table term-name))
end-terms)))))))
(make-object grammar%
new-prods
(map car start-prods)
terms
(append starts (append end-non-terms non-terms))
(map (λ (term-name) (hash-ref term-table term-name)) end-terms)))

@ -1,277 +1,252 @@
(module lalr mzscheme
#lang racket/base
(require "lr0.rkt"
"grammar.rkt"
racket/list
racket/class)
;; Compute LALR lookaheads from DeRemer and Pennello 1982
;; Compute LALR lookaheads from DeRemer and Pennello 1982
(require "lr0.rkt"
"grammar.rkt"
mzlib/list
mzlib/class)
(provide compute-LA)
(provide compute-LA)
;; compute-DR: LR0-automaton * grammar -> (trans-key -> term set)
;; computes for each state, non-term transition pair, the terminals
;; which can transition out of the resulting state
;; output term set is represented in bit-vector form
(define (compute-DR a g)
(lambda (tk)
(let ((r (send a run-automaton (trans-key-st tk) (trans-key-gs tk))))
(term-list->bit-vector
(filter
(lambda (term)
(send a run-automaton r term))
(send g get-terms))))))
;; compute-DR: LR0-automaton * grammar -> (trans-key -> term set)
;; computes for each state, non-term transition pair, the terminals
;; which can transition out of the resulting state
;; output term set is represented in bit-vector form
(define ((compute-DR a g) tk)
(define r (send a run-automaton (trans-key-st tk) (trans-key-gs tk)))
(term-list->bit-vector
(filter (λ (term) (send a run-automaton r term)) (send g get-terms))))
;; compute-reads:
;; LR0-automaton * grammar -> (trans-key -> trans-key list)
(define (compute-reads a g)
(let ((nullable-non-terms
(filter (lambda (nt) (send g nullable-non-term? nt))
(send g get-non-terms))))
(lambda (tk)
(let ((r (send a run-automaton (trans-key-st tk) (trans-key-gs tk))))
(map (lambda (x) (make-trans-key r x))
(filter (lambda (non-term) (send a run-automaton r non-term))
nullable-non-terms))))))
;; compute-reads:
;; LR0-automaton * grammar -> (trans-key -> trans-key list)
(define (compute-reads a g)
(define nullable-non-terms (filter (λ (nt) (send g nullable-non-term? nt)) (send g get-non-terms)))
(λ (tk)
(define r (send a run-automaton (trans-key-st tk) (trans-key-gs tk)))
(for/list ([non-term (in-list nullable-non-terms)]
#:when (send a run-automaton r non-term))
(make-trans-key r non-term))))
;; compute-read: LR0-automaton * grammar -> (trans-key -> term set)
;; output term set is represented in bit-vector form
(define (compute-read a g)
(let* ((dr (compute-DR a g))
(reads (compute-reads a g)))
(digraph-tk->terml (send a get-mapped-non-term-keys)
reads
dr
(send a get-num-states))))
;; returns the list of all k such that state k transitions to state start on the
;; transitions in rhs (in order)
(define (run-lr0-backward a rhs dot-pos start num-states)
(let loop ((states (list start))
(i (sub1 dot-pos)))
(cond
((< i 0) states)
(else (loop (send a run-automaton-back states (vector-ref rhs i))
(sub1 i))))))
;; compute-read: LR0-automaton * grammar -> (trans-key -> term set)
;; output term set is represented in bit-vector form
(define (compute-read a g)
(define dr (compute-DR a g))
(define reads (compute-reads a g))
(digraph-tk->terml (send a get-mapped-non-term-keys)
reads
dr
(send a get-num-states)))
;; returns the list of all k such that state k transitions to state start on the
;; transitions in rhs (in order)
(define (run-lr0-backward a rhs dot-pos start num-states)
(let loop ([states (list start)]
[i (sub1 dot-pos)])
(cond
[(< i 0) states]
[else (loop (send a run-automaton-back states (vector-ref rhs i))
(sub1 i))])))
;; prod->items-for-include: grammar * prod * non-term -> lr0-item list
;; returns the list of all (B -> beta . nt gamma) such that prod = (B -> beta nt gamma)
;; and gamma =>* epsilon
(define (prod->items-for-include g prod nt)
(let* ((rhs (prod-rhs prod))
(rhs-l (vector-length rhs)))
(append (if (and (> rhs-l 0) (eq? nt (vector-ref rhs (sub1 rhs-l))))
(list (make-item prod (sub1 rhs-l)))
null)
(let loop ((i (sub1 rhs-l)))
(cond
((and (> i 0)
(non-term? (vector-ref rhs i))
(send g nullable-non-term? (vector-ref rhs i)))
(if (eq? nt (vector-ref rhs (sub1 i)))
(cons (make-item prod (sub1 i))
(loop (sub1 i)))
(loop (sub1 i))))
(else null))))))
;; prod->items-for-include: grammar * prod * non-term -> lr0-item list
;; returns the list of all (B -> beta . nt gamma) such that prod = (B -> beta nt gamma)
;; and gamma =>* epsilon
(define (prod->items-for-include g prod nt)
(define rhs (prod-rhs prod))
(define rhs-l (vector-length rhs))
(append (if (and (> rhs-l 0) (eq? nt (vector-ref rhs (sub1 rhs-l))))
(list (make-item prod (sub1 rhs-l)))
null)
(let loop ([i (sub1 rhs-l)])
(cond
[(and (> i 0)
(non-term? (vector-ref rhs i))
(send g nullable-non-term? (vector-ref rhs i)))
(if (eq? nt (vector-ref rhs (sub1 i)))
(cons (make-item prod (sub1 i))
(loop (sub1 i)))
(loop (sub1 i)))]
[else null]))))
;; prod-list->items-for-include: grammar * prod list * non-term -> lr0-item list
;; return the list of all (B -> beta . nt gamma) such that (B -> beta nt gamma) in prod-list
;; and gamma =>* epsilon
(define (prod-list->items-for-include g prod-list nt)
(apply append (map (lambda (prod) (prod->items-for-include g prod nt)) prod-list)))
;; prod-list->items-for-include: grammar * prod list * non-term -> lr0-item list
;; return the list of all (B -> beta . nt gamma) such that (B -> beta nt gamma) in prod-list
;; and gamma =>* epsilon
(define (prod-list->items-for-include g prod-list nt)
(apply append (map (λ (prod) (prod->items-for-include g prod nt)) prod-list)))
;; comput-includes: lr0-automaton * grammar -> (trans-key -> trans-key list)
(define (compute-includes a g)
(let ((num-states (send a get-num-states))
(items-for-input-nt (make-vector (send g get-num-non-terms) null)))
(for-each
(lambda (input-nt)
(vector-set! items-for-input-nt (non-term-index input-nt)
(prod-list->items-for-include g (send g get-prods) input-nt)))
(send g get-non-terms))
(lambda (tk)
(let* ((goal-state (trans-key-st tk))
(non-term (trans-key-gs tk))
(items (vector-ref items-for-input-nt (non-term-index non-term))))
(trans-key-list-remove-dups
(apply append
(map (lambda (item)
(let* ((prod (item-prod item))
(rhs (prod-rhs prod))
(lhs (prod-lhs prod)))
(map (lambda (state)
(make-trans-key state lhs))
(run-lr0-backward a
rhs
(item-dot-pos item)
goal-state
num-states))))
items)))))))
;; comput-includes: lr0-automaton * grammar -> (trans-key -> trans-key list)
(define (compute-includes a g)
(define num-states (send a get-num-states))
(define items-for-input-nt (make-vector (send g get-num-non-terms) null))
(for ([input-nt (in-list (send g get-non-terms))])
(vector-set! items-for-input-nt (non-term-index input-nt)
(prod-list->items-for-include g (send g get-prods) input-nt)))
(λ (tk)
(define goal-state (trans-key-st tk))
(define non-term (trans-key-gs tk))
(define items (vector-ref items-for-input-nt (non-term-index non-term)))
(trans-key-list-remove-dups
(apply append
(for/list ([item (in-list items)])
(define prod (item-prod item))
(define rhs (prod-rhs prod))
(define lhs (prod-lhs prod))
(map (λ (state) (make-trans-key state lhs))
(run-lr0-backward a
rhs
(item-dot-pos item)
goal-state
num-states)))))))
;; compute-lookback: lr0-automaton * grammar -> (kernel * proc -> trans-key list)
(define (compute-lookback a g)
(let ((num-states (send a get-num-states)))
(lambda (state prod)
(map (lambda (k) (make-trans-key k (prod-lhs prod)))
(run-lr0-backward a (prod-rhs prod) (vector-length (prod-rhs prod)) state num-states)))))
;; compute-lookback: lr0-automaton * grammar -> (kernel * proc -> trans-key list)
(define (compute-lookback a g)
(define num-states (send a get-num-states))
(λ (state prod)
(map (λ (k) (make-trans-key k (prod-lhs prod)))
(run-lr0-backward a (prod-rhs prod) (vector-length (prod-rhs prod)) state num-states))))
;; compute-follow: LR0-automaton * grammar -> (trans-key -> term set)
;; output term set is represented in bit-vector form
(define (compute-follow a g includes)
(let ((read (compute-read a g)))
(digraph-tk->terml (send a get-mapped-non-term-keys)
includes
read
(send a get-num-states))))
;; compute-follow: LR0-automaton * grammar -> (trans-key -> term set)
;; output term set is represented in bit-vector form
(define (compute-follow a g includes)
(define read (compute-read a g))
(digraph-tk->terml (send a get-mapped-non-term-keys)
includes
read
(send a get-num-states)))
;; compute-LA: LR0-automaton * grammar -> kernel * prod -> term set
;; output term set is represented in bit-vector form
(define (compute-LA a g)
(let* ((includes (compute-includes a g))
(lookback (compute-lookback a g))
(follow (compute-follow a g includes)))
(lambda (k p)
(let* ((l (lookback k p))
(f (map follow l)))
(apply bitwise-ior (cons 0 f))))))
;; compute-LA: LR0-automaton * grammar -> kernel * prod -> term set
;; output term set is represented in bit-vector form
(define (compute-LA a g)
(define includes (compute-includes a g))
(define lookback (compute-lookback a g))
(define follow (compute-follow a g includes))
(λ (k p)
(define l (lookback k p))
(define f (map follow l))
(apply bitwise-ior (cons 0 f))))
(define (print-DR dr a g)
(print-input-st-sym dr "DR" a g print-output-terms))
(define (print-Read Read a g)
(print-input-st-sym Read "Read" a g print-output-terms))
(define (print-includes i a g)
(print-input-st-sym i "includes" a g print-output-st-nt))
(define (print-lookback l a g)
(print-input-st-prod l "lookback" a g print-output-st-nt))
(define (print-follow f a g)
(print-input-st-sym f "follow" a g print-output-terms))
(define (print-LA l a g)
(print-input-st-prod l "LA" a g print-output-terms))
(define (print-DR dr a g)
(print-input-st-sym dr "DR" a g print-output-terms))
(define (print-Read Read a g)
(print-input-st-sym Read "Read" a g print-output-terms))
(define (print-includes i a g)
(print-input-st-sym i "includes" a g print-output-st-nt))
(define (print-lookback l a g)
(print-input-st-prod l "lookback" a g print-output-st-nt))
(define (print-follow f a g)
(print-input-st-sym f "follow" a g print-output-terms))
(define (print-LA l a g)
(print-input-st-prod l "LA" a g print-output-terms))
(define (print-input-st-sym f name a g print-output)
(printf "~a:\n" name)
(send a for-each-state
(lambda (state)
(for-each
(lambda (non-term)
(let ((res (f (make-trans-key state non-term))))
(if (not (null? res))
(printf "~a(~a, ~a) = ~a\n"
name
state
(gram-sym-symbol non-term)
(print-output res)))))
(send g get-non-terms))))
(newline))
(define (print-input-st-sym f name a g print-output)
(printf "~a:\n" name)
(send a for-each-state
(λ (state)
(for-each
(λ (non-term)
(let ([res (f (make-trans-key state non-term))])
(when (not (null? res))
(printf "~a(~a, ~a) = ~a\n"
name
state
(gram-sym-symbol non-term)
(print-output res)))))
(send g get-non-terms))))
(newline))
(define (print-input-st-prod f name a g print-output)
(printf "~a:\n" name)
(send a for-each-state
(lambda (state)
(for-each
(lambda (non-term)
(define (print-input-st-prod f name a g print-output)
(printf "~a:\n" name)
(send a for-each-state
(λ (state)
(for-each
(lambda (prod)
(let ((res (f state prod)))
(if (not (null? res))
(printf "~a(~a, ~a) = ~a\n"
name
(kernel-index state)
(prod-index prod)
(print-output res)))))
(send g get-prods-for-non-term non-term)))
(send g get-non-terms)))))
(λ (non-term)
(for-each
(λ (prod)
(let ([res (f state prod)])
(when (not (null? res))
(printf "~a(~a, ~a) = ~a\n"
name
(kernel-index state)
(prod-index prod)
(print-output res)))))
(send g get-prods-for-non-term non-term)))
(send g get-non-terms)))))
(define (print-output-terms r)
(map
(lambda (p)
(gram-sym-symbol p))
r))
(define (print-output-terms r)
(map gram-sym-symbol r))
(define (print-output-st-nt r)
(map
(lambda (p)
(list
(kernel-index (trans-key-st p))
(gram-sym-symbol (trans-key-gs p))))
r))
(define (print-output-st-nt r)
(map (λ (p) (list (kernel-index (trans-key-st p)) (gram-sym-symbol (trans-key-gs p)))) r))
;; init-tk-map : int -> (vectorof hashtable?)
(define (init-tk-map n)
(let ((v (make-vector n #f)))
(let loop ((i (sub1 (vector-length v))))
(when (>= i 0)
(vector-set! v i (make-hash-table))
(loop (sub1 i))))
v))
;; init-tk-map : int -> (vectorof hashtable?)
(define (init-tk-map n)
(define v (make-vector n #f))
(let loop ([i (sub1 (vector-length v))])
(when (>= i 0)
(vector-set! v i (make-hasheq))
(loop (sub1 i))))
v)
;; lookup-tk-map : (vectorof (symbol? int hashtable)) -> trans-key? -> int
(define (lookup-tk-map map)
(lambda (tk)
(let ((st (trans-key-st tk))
(gs (trans-key-gs tk)))
(hash-table-get (vector-ref map (kernel-index st))
(gram-sym-symbol gs)
(lambda () 0)))))
;; lookup-tk-map : (vectorof (symbol? int hashtable)) -> trans-key? -> int
(define ((lookup-tk-map map) tk)
(define st (trans-key-st tk))
(define gs (trans-key-gs tk))
(hash-ref (vector-ref map (kernel-index st))
(gram-sym-symbol gs)
(λ () 0)))
;; add-tk-map : (vectorof (symbol? int hashtable)) -> trans-key int ->
(define (add-tk-map map)
(lambda (tk v)
(let ((st (trans-key-st tk))
(gs (trans-key-gs tk)))
(hash-table-put! (vector-ref map (kernel-index st))
(gram-sym-symbol gs)
v))))
;; add-tk-map : (vectorof (symbol? int hashtable)) -> trans-key int ->
(define ((add-tk-map map) tk v)
(define st (trans-key-st tk))
(define gs (trans-key-gs tk))
(hash-set! (vector-ref map (kernel-index st))
(gram-sym-symbol gs)
v))
;; digraph-tk->terml:
;; (trans-key list) * (trans-key -> trans-key list) * (trans-key -> term list) * int * int * int
;; -> (trans-key -> term list)
;; DeRemer and Pennello 1982
;; Computes (f x) = (f- x) union Union{(f y) | y in (edges x)}
;; A specialization of digraph in the file graph.rkt
(define (digraph-tk->terml nodes edges f- num-states)
(letrec [
;; Will map elements of trans-key to term sets represented as bit vectors
(results (init-tk-map num-states))
;; digraph-tk->terml:
;; (trans-key list) * (trans-key -> trans-key list) * (trans-key -> term list) * int * int * int
;; -> (trans-key -> term list)
;; DeRemer and Pennello 1982
;; Computes (f x) = (f- x) union Union{(f y) | y in (edges x)}
;; A specialization of digraph in the file graph.rkt
(define (digraph-tk->terml nodes edges f- num-states)
;; Will map elements of trans-key to term sets represented as bit vectors
(define results (init-tk-map num-states))
;; Maps elements of trans-keys to integers.
(N (init-tk-map num-states))
;; Maps elements of trans-keys to integers.
(define N (init-tk-map num-states))
(get-N (lookup-tk-map N))
(set-N (add-tk-map N))
(get-f (lookup-tk-map results))
(set-f (add-tk-map results))
(define get-N (lookup-tk-map N))
(define set-N (add-tk-map N))
(define get-f (lookup-tk-map results))
(define set-f (add-tk-map results))
(stack null)
(push (lambda (x)
(set! stack (cons x stack))))
(pop (lambda ()
(begin0
(car stack)
(set! stack (cdr stack)))))
(depth (lambda () (length stack)))
(define stack null)
(define (push x) (set! stack (cons x stack)))
(define (pop) (begin0
(car stack)
(set! stack (cdr stack))))
(define (depth) (length stack))
;; traverse: 'a ->
(define (traverse x)
(push x)
(let ([d (depth)])
(set-N x d)
(set-f x (f- x))
(for-each (λ (y)
(when (= 0 (get-N y))
(traverse y))
(set-f x (bitwise-ior (get-f x) (get-f y)))
(set-N x (min (get-N x) (get-N y))))
(edges x))
(when (= d (get-N x))
(let loop ([p (pop)])
(set-N p +inf.0)
(set-f p (get-f x))
(unless (equal? x p)
(loop (pop)))))))
;; traverse: 'a ->
(traverse
(lambda (x)
(push x)
(let ((d (depth)))
(set-N x d)
(set-f x (f- x))
(for-each (lambda (y)
(when (= 0 (get-N y))
(traverse y))
(set-f x (bitwise-ior (get-f x) (get-f y)))
(set-N x (min (get-N x) (get-N y))))
(edges x))
(when (= d (get-N x))
(let loop ((p (pop)))
(set-N p +inf.0)
(set-f p (get-f x))
(unless (equal? x p)
(loop (pop))))))))]
(for-each (lambda (x)
(when (= 0 (get-N x))
(traverse x)))
nodes)
get-f))
)
(for ([x (in-list nodes)]
#:when (zero? (get-N x)))
(traverse x))
get-f)

@ -1,372 +1,314 @@
(module lr0 mzscheme
#lang racket/base
(require "grammar.rkt"
"graph.rkt"
racket/list
racket/class)
;; Handle the LR0 automaton
;; Handle the LR0 automaton
(require "grammar.rkt"
"graph.rkt"
mzlib/list
mzlib/class)
(provide build-lr0-automaton lr0%
(struct trans-key (st gs)) trans-key-list-remove-dups
kernel-items kernel-index)
(provide build-lr0-automaton lr0%
(struct-out trans-key) trans-key-list-remove-dups
kernel-items kernel-index)
;; kernel = (make-kernel (LR1-item list) index)
;; the list must be kept sorted according to item<? so that equal? can
;; be used to compare kernels
;; Each kernel is assigned a unique index, 0 <= index < number of states
;; trans-key = (make-trans-key kernel gram-sym)
(define-struct kernel (items index) (make-inspector))
(define-struct trans-key (st gs) (make-inspector))
;; kernel = (make-kernel (LR1-item list) index)
;; the list must be kept sorted according to item<? so that equal? can
;; be used to compare kernels
;; Each kernel is assigned a unique index, 0 <= index < number of states
;; trans-key = (make-trans-key kernel gram-sym)
(define-struct kernel (items index) #:inspector (make-inspector))
(define-struct trans-key (st gs) #:inspector (make-inspector))
(define (trans-key<? a b)
(let ((kia (kernel-index (trans-key-st a)))
(kib (kernel-index (trans-key-st b))))
(or (< kia kib)
(and (= kia kib)
(< (non-term-index (trans-key-gs a))
(non-term-index (trans-key-gs b)))))))
(define (trans-key<? a b)
(define kia (kernel-index (trans-key-st a)))
(define kib (kernel-index (trans-key-st b)))
(or (< kia kib)
(and (= kia kib)
(< (non-term-index (trans-key-gs a))
(non-term-index (trans-key-gs b))))))
(define (trans-key-list-remove-dups tkl)
(let loop ((sorted (sort tkl trans-key<?)))
(cond
((null? sorted) null)
((null? (cdr sorted)) sorted)
(else
(if (and (= (non-term-index (trans-key-gs (car sorted)))
(non-term-index (trans-key-gs (cadr sorted))))
(= (kernel-index (trans-key-st (car sorted)))
(kernel-index (trans-key-st (cadr sorted)))))
(loop (cdr sorted))
(cons (car sorted) (loop (cdr sorted))))))))
(define (trans-key-list-remove-dups tkl)
(let loop ([sorted (sort tkl trans-key<?)])
(cond
[(null? sorted) null]
[(null? (cdr sorted)) sorted]
[else
(if (and (= (non-term-index (trans-key-gs (car sorted)))
(non-term-index (trans-key-gs (cadr sorted))))
(= (kernel-index (trans-key-st (car sorted)))
(kernel-index (trans-key-st (cadr sorted)))))
(loop (cdr sorted))
(cons (car sorted) (loop (cdr sorted))))])))
;; build-transition-table : int (listof (cons/c trans-key X) ->
;; (vectorof (symbol X hashtable))
(define (build-transition-table num-states assoc)
(let ((transitions (make-vector num-states #f)))
(let loop ((i (sub1 (vector-length transitions))))
(when (>= i 0)
(vector-set! transitions i (make-hash-table))
(loop (sub1 i))))
(for-each
(lambda (trans-key/kernel)
(let ((tk (car trans-key/kernel)))
(hash-table-put! (vector-ref transitions (kernel-index (trans-key-st tk)))
(gram-sym-symbol (trans-key-gs tk))
(cdr trans-key/kernel))))
assoc)
transitions))
;; build-transition-table : int (listof (cons/c trans-key X) ->
;; (vectorof (symbol X hashtable))
(define (build-transition-table num-states assoc)
(define transitions (make-vector num-states #f))
(let loop ([i (sub1 (vector-length transitions))])
(when (>= i 0)
(vector-set! transitions i (make-hasheq))
(loop (sub1 i))))
(for ([trans-key/kernel (in-list assoc)])
(define tk (car trans-key/kernel))
(hash-set! (vector-ref transitions (kernel-index (trans-key-st tk)))
(gram-sym-symbol (trans-key-gs tk))
(cdr trans-key/kernel)))
transitions)
;; reverse-assoc : (listof (cons/c trans-key? kernel?)) ->
;; (listof (cons/c trans-key? (listof kernel?)))
(define (reverse-assoc assoc)
(let ((reverse-hash (make-hash-table 'equal))
(hash-table-add!
(lambda (ht k v)
(hash-table-put! ht k (cons v (hash-table-get ht k (lambda () null)))))))
(for-each
(lambda (trans-key/kernel)
(let ((tk (car trans-key/kernel)))
(hash-table-add! reverse-hash
(make-trans-key (cdr trans-key/kernel)
(trans-key-gs tk))
(trans-key-st tk))))
assoc)
(hash-table-map reverse-hash cons)))
;; reverse-assoc : (listof (cons/c trans-key? kernel?)) ->
;; (listof (cons/c trans-key? (listof kernel?)))
(define (reverse-assoc assoc)
(define reverse-hash (make-hash))
(define (hash-table-add! ht k v)
(hash-set! ht k (cons v (hash-ref ht k (λ () null)))))
(for ([trans-key/kernel (in-list assoc)])
(define tk (car trans-key/kernel))
(hash-table-add! reverse-hash
(make-trans-key (cdr trans-key/kernel)
(trans-key-gs tk))
(trans-key-st tk)))
(hash-map reverse-hash cons))
;; kernel-list-remove-duplicates
;; LR0-automaton = object of class lr0%
(define lr0%
(class object%
(super-instantiate ())
;; term-assoc : (listof (cons/c trans-key? kernel?))
;; non-term-assoc : (listof (cons/c trans-key? kernel?))
;; states : (vectorof kernel?)
;; epsilons : ???
(init-field term-assoc non-term-assoc states epsilons)
;; kernel-list-remove-duplicates
;; LR0-automaton = object of class lr0%
(define lr0%
(class object%
(super-instantiate ())
;; term-assoc : (listof (cons/c trans-key? kernel?))
;; non-term-assoc : (listof (cons/c trans-key? kernel?))
;; states : (vectorof kernel?)
;; epsilons : ???
(init-field term-assoc non-term-assoc states epsilons)
(define transitions (build-transition-table (vector-length states)
(append term-assoc non-term-assoc)))
(define transitions (build-transition-table (vector-length states)
(append term-assoc non-term-assoc)))
(define reverse-term-assoc (reverse-assoc term-assoc))
(define reverse-non-term-assoc (reverse-assoc non-term-assoc))
(define reverse-transitions
(build-transition-table (vector-length states)
(append reverse-term-assoc reverse-non-term-assoc)))
(define reverse-term-assoc (reverse-assoc term-assoc))
(define reverse-non-term-assoc (reverse-assoc non-term-assoc))
(define reverse-transitions
(build-transition-table (vector-length states)
(append reverse-term-assoc reverse-non-term-assoc)))
(define mapped-non-terms (map car non-term-assoc))
(define mapped-non-terms (map car non-term-assoc))
(define/public (get-mapped-non-term-keys)
mapped-non-terms)
(define/public (get-mapped-non-term-keys)
mapped-non-terms)
(define/public (get-num-states)
(vector-length states))
(define/public (get-num-states)
(vector-length states))
(define/public (get-epsilon-trans)
epsilons)
(define/public (get-epsilon-trans)
epsilons)
(define/public (get-transitions)
(append term-assoc non-term-assoc))
(define/public (get-transitions)
(append term-assoc non-term-assoc))
;; for-each-state : (state ->) ->
;; Iteration over the states in an automaton
(define/public (for-each-state f)
(let ((num-states (vector-length states)))
(let loop ((i 0))
(if (< i num-states)
(begin
(f (vector-ref states i))
(loop (add1 i)))))))
;; for-each-state : (state ->) ->
;; Iteration over the states in an automaton
(define/public (for-each-state f)
(define num-states (vector-length states))
(let loop ([i 0])
(when (< i num-states)
(f (vector-ref states i))
(loop (add1 i)))))
;; run-automaton: kernel? gram-sym? -> (union kernel #f)
;; returns the state reached from state k on input s, or #f when k
;; has no transition on s
(define/public (run-automaton k s)
(hash-table-get (vector-ref transitions (kernel-index k))
(gram-sym-symbol s)
(lambda () #f)))
;; run-automaton: kernel? gram-sym? -> (union kernel #f)
;; returns the state reached from state k on input s, or #f when k
;; has no transition on s
(define/public (run-automaton k s)
(hash-ref (vector-ref transitions (kernel-index k))
(gram-sym-symbol s)
(λ () #f)))
;; run-automaton-back : (listof kernel?) gram-sym? -> (listof kernel)
;; returns the list of states that can reach k by transitioning on s.
(define/public (run-automaton-back k s)
(apply append
(map
(lambda (k)
(hash-table-get (vector-ref reverse-transitions (kernel-index k))
(gram-sym-symbol s)
(lambda () null)))
k)))))
;; run-automaton-back : (listof kernel?) gram-sym? -> (listof kernel)
;; returns the list of states that can reach k by transitioning on s.
(define/public (run-automaton-back k s)
(for*/list ([k (in-list k)]
[val (in-list (hash-ref (vector-ref reverse-transitions (kernel-index k))
(gram-sym-symbol s)
(λ () null)))])
val))))
(define (union comp<?)
(letrec ((union
(lambda (l1 l2)
(cond
((null? l1) l2)
((null? l2) l1)
(else (let ((c1 (car l1))
(c2 (car l2)))
(cond
((comp<? c1 c2)
(cons c1 (union (cdr l1) l2)))
((comp<? c2 c1)
(cons c2 (union l1 (cdr l2))))
(else (union (cdr l1) l2)))))))))
union))
(define ((union comp<?) l1 l2)
(let loop ([l1 l1] [l2 l2])
(cond
[(null? l1) l2]
[(null? l2) l1]
[else (define c1 (car l1))
(define c2 (car l2))
(cond
[(comp<? c1 c2) (cons c1 (loop (cdr l1) l2))]
[(comp<? c2 c1) (cons c2 (loop l1 (cdr l2)))]
[else (loop (cdr l1) l2)])])))
;; The kernels in the automaton are represented cannonically.
;; That is (equal? a b) <=> (eq? a b)
(define (kernel->string k)
(apply string-append
`("{" ,@(map (lambda (i) (string-append (item->string i) ", "))
(kernel-items k))
"}")))
;; The kernels in the automaton are represented cannonically.
;; That is (equal? a b) <=> (eq? a b)
(define (kernel->string k)
(apply string-append
`("{" ,@(map (λ (i) (string-append (item->string i) ", "))
(kernel-items k))
"}")))
;; build-LR0-automaton: grammar -> LR0-automaton
;; Constructs the kernels of the sets of LR(0) items of g
(define (build-lr0-automaton grammar)
; (printf "LR(0) automaton:\n")
(letrec (
(epsilons (make-hash-table 'equal))
(grammar-symbols (append (send grammar get-non-terms)
(send grammar get-terms)))
;; first-non-term: non-term -> non-term list
;; given a non-terminal symbol C, return those non-terminal
;; symbols A s.t. C -> An for some string of terminals and
;; non-terminals n where -> means a rightmost derivation in many
;; steps. Assumes that each non-term can be reduced to a string
;; of terms.
(first-non-term
(digraph (send grammar get-non-terms)
(lambda (nt)
(filter non-term?
(map (lambda (prod)
(sym-at-dot (make-item prod 0)))
(send grammar get-prods-for-non-term nt))))
(lambda (nt) (list nt))
(union non-term<?)
(lambda () null)))
;; build-LR0-automaton: grammar -> LR0-automaton
;; Constructs the kernels of the sets of LR(0) items of g
(define (build-lr0-automaton grammar)
; (printf "LR(0) automaton:\n")
(define epsilons (make-hash))
(define grammar-symbols (append (send grammar get-non-terms)
(send grammar get-terms)))
;; first-non-term: non-term -> non-term list
;; given a non-terminal symbol C, return those non-terminal
;; symbols A s.t. C -> An for some string of terminals and
;; non-terminals n where -> means a rightmost derivation in many
;; steps. Assumes that each non-term can be reduced to a string
;; of terms.
(define first-non-term
(digraph (send grammar get-non-terms)
(λ (nt)
(filter non-term?
(map (λ (prod) (sym-at-dot (make-item prod 0)))
(send grammar get-prods-for-non-term nt))))
(λ (nt) (list nt))
(union non-term<?)
(λ () null)))
;; closure: LR1-item list -> LR1-item list
;; Creates a set of items containing i s.t. if A -> n.Xm is in it,
;; X -> .o is in it too.
(LR0-closure
(lambda (i)
(cond
((null? i) null)
(else
(let ((next-gsym (sym-at-dot (car i))))
(cond
((non-term? next-gsym)
(cons (car i)
(append
(apply append
(map (lambda (non-term)
(map (lambda (x)
(make-item x 0))
(send grammar
get-prods-for-non-term
non-term)))
(first-non-term next-gsym)))
(LR0-closure (cdr i)))))
(else
(cons (car i) (LR0-closure (cdr i))))))))))
;; maps trans-keys to kernels
(automaton-term null)
(automaton-non-term null)
;; closure: LR1-item list -> LR1-item list
;; Creates a set of items containing i s.t. if A -> n.Xm is in it,
;; X -> .o is in it too.
(define (LR0-closure i)
(cond
[(null? i) null]
[else
(define next-gsym (sym-at-dot (car i)))
(cond
[(non-term? next-gsym)
(cons (car i)
(append
(for*/list ([non-term (in-list (first-non-term next-gsym))]
[x (in-list (send grammar
get-prods-for-non-term
non-term))])
(make-item x 0))
(LR0-closure (cdr i))))]
[else (cons (car i) (LR0-closure (cdr i)))])]))
;; maps trans-keys to kernels
(define automaton-term null)
(define automaton-non-term null)
;; keeps the kernels we have seen, so we can have a unique
;; list for each kernel
(kernels (make-hash-table 'equal))
(counter 0)
;; keeps the kernels we have seen, so we can have a unique
;; list for each kernel
(define kernels (make-hash))
(define counter 0)
;; goto: LR1-item list -> LR1-item list list
;; creates new kernels by moving the dot in each item in the
;; LR0-closure of kernel to the right, and grouping them by
;; the term/non-term moved over. Returns the kernels not
;; yet seen, and places the trans-keys into automaton
(goto
(lambda (kernel)
(let (
;; maps a gram-syms to a list of items
(table (make-hash-table))
;; goto: LR1-item list -> LR1-item list list
;; creates new kernels by moving the dot in each item in the
;; LR0-closure of kernel to the right, and grouping them by
;; the term/non-term moved over. Returns the kernels not
;; yet seen, and places the trans-keys into automaton
(define (goto kernel)
;; maps a gram-syms to a list of items
(define table (make-hasheq))
;; add-item!:
;; (symbol (listof item) hashtable) item? ->
;; adds i into the table grouped with the grammar
;; symbol following its dot
(add-item!
(lambda (table i)
(let ((gs (sym-at-dot i)))
(cond
(gs
(let ((already
(hash-table-get table
(gram-sym-symbol gs)
(lambda () null))))
(unless (member i already)
(hash-table-put! table
(gram-sym-symbol gs)
(cons i already)))))
((= 0 (vector-length (prod-rhs (item-prod i))))
(let ((current (hash-table-get epsilons
kernel
(lambda () null))))
(hash-table-put! epsilons
kernel
(cons i current)))))))))
;; Group the items of the LR0 closure of the kernel
;; by the character after the dot
(for-each (lambda (item)
(add-item! table item))
(LR0-closure (kernel-items kernel)))
;; add-item!:
;; (symbol (listof item) hashtable) item? ->
;; adds i into the table grouped with the grammar
;; symbol following its dot
(define (add-item! table i)
(define gs (sym-at-dot i))
(cond
[gs (define already (hash-ref table (gram-sym-symbol gs) (λ () null)))
(unless (member i already)
(hash-set! table (gram-sym-symbol gs) (cons i already)))]
((zero? (vector-length (prod-rhs (item-prod i))))
(define current (hash-ref epsilons kernel (λ () null)))
(hash-set! epsilons kernel (cons i current)))))
;; Group the items of the LR0 closure of the kernel
;; by the character after the dot
(for ([item (in-list (LR0-closure (kernel-items kernel)))])
(add-item! table item))
;; each group is a new kernel, with the dot advanced.
;; sorts the items in a kernel so kernels can be compared
;; with equal? for using the table kernels to make sure
;; only one representitive of each kernel is created
(filter
(lambda (x) x)
(map
(lambda (i)
(let* ((gs (car i))
(items (cadr i))
(new #f)
(new-kernel (sort
(filter (lambda (x) x)
(map move-dot-right items))
item<?))
(unique-kernel (hash-table-get
kernels
new-kernel
(lambda ()
(let ((k (make-kernel
new-kernel
counter)))
;; each group is a new kernel, with the dot advanced.
;; sorts the items in a kernel so kernels can be compared
;; with equal? for using the table kernels to make sure
;; only one representitive of each kernel is created
(define is
(let loop ([gsyms grammar-symbols])
(cond
[(null? gsyms) null]
[else
(define items (hash-ref table (gram-sym-symbol (car gsyms)) (λ () null)))
(cond
[(null? items) (loop (cdr gsyms))]
[else (cons (list (car gsyms) items)
(loop (cdr gsyms)))])])))
(filter
values
(for/list ([i (in-list is)])
(define gs (car i))
(define items (cadr i))
(define new #f)
(define new-kernel (sort (filter values (map move-dot-right items)) item<?))
(define unique-kernel (hash-ref kernels new-kernel
(λ ()
(define k (make-kernel new-kernel counter))
(set! new #t)
(set! counter (add1 counter))
(hash-table-put! kernels
new-kernel
k)
k)))))
(cond
((term? gs)
(set! automaton-term (cons (cons (make-trans-key kernel gs)
unique-kernel)
automaton-term)))
(else
(set! automaton-non-term (cons (cons (make-trans-key kernel gs)
unique-kernel)
automaton-non-term))))
#;(printf "~a -> ~a on ~a\n"
(kernel->string kernel)
(kernel->string unique-kernel)
(gram-sym-symbol gs))
(if new
unique-kernel
#f)))
(let loop ((gsyms grammar-symbols))
(cond
((null? gsyms) null)
(else
(let ((items (hash-table-get table
(gram-sym-symbol (car gsyms))
(lambda () null))))
(cond
((null? items) (loop (cdr gsyms)))
(else
(cons (list (car gsyms) items)
(loop (cdr gsyms))))))))))))))
(hash-set! kernels new-kernel k)
k)))
(if (term? gs)
(set! automaton-term (cons (cons (make-trans-key kernel gs)
unique-kernel)
automaton-term))
(set! automaton-non-term (cons (cons (make-trans-key kernel gs)
unique-kernel)
automaton-non-term)))
#;(printf "~a -> ~a on ~a\n"
(kernel->string kernel)
(kernel->string unique-kernel)
(gram-sym-symbol gs))
(and new unique-kernel))))
(starts
(map (lambda (init-prod) (list (make-item init-prod 0)))
(send grammar get-init-prods)))
(startk
(map (lambda (start)
(let ((k (make-kernel start counter)))
(hash-table-put! kernels start k)
(set! counter (add1 counter))
k))
starts))
(new-kernels (make-queue)))
(define starts (map (λ (init-prod) (list (make-item init-prod 0)))
(send grammar get-init-prods)))
(define startk (for/list ([start (in-list starts)])
(define k (make-kernel start counter))
(hash-set! kernels start k)
(set! counter (add1 counter))
k))
(define new-kernels (make-queue))
(let loop ([old-kernels startk]
[seen-kernels null])
(cond
[(and (empty-queue? new-kernels) (null? old-kernels))
(make-object lr0% automaton-term automaton-non-term
(list->vector (reverse seen-kernels)) epsilons)]
[(null? old-kernels) (loop (deq! new-kernels) seen-kernels)]
[else
(enq! new-kernels (goto (car old-kernels)))
(loop (cdr old-kernels) (cons (car old-kernels) seen-kernels))])))
(let loop ((old-kernels startk)
(seen-kernels null))
(cond
((and (empty-queue? new-kernels) (null? old-kernels))
(make-object lr0%
automaton-term
automaton-non-term
(list->vector (reverse seen-kernels))
epsilons))
((null? old-kernels)
(loop (deq! new-kernels) seen-kernels))
(else
(enq! new-kernels (goto (car old-kernels)))
(loop (cdr old-kernels) (cons (car old-kernels) seen-kernels)))))))
(define-struct q (f l) #:inspector (make-inspector) #:mutable)
(define (empty-queue? q) (null? (q-f q)))
(define (make-queue) (make-q null null))
(define (enq! q i)
(cond
[(empty-queue? q)
(let ([i (mcons i null)])
(set-q-l! q i)
(set-q-f! q i))]
[else
(set-mcdr! (q-l q) (mcons i null))
(set-q-l! q (mcdr (q-l q)))]))
(define (deq! q)
(begin0
(mcar (q-f q))
(set-q-f! q (mcdr (q-f q)))))
(define-struct q (f l) (make-inspector))
(define (empty-queue? q)
(null? (q-f q)))
(define (make-queue)
(make-q null null))
(define (enq! q i)
(if (empty-queue? q)
(let ((i (mcons i null)))
(set-q-l! q i)
(set-q-f! q i))
(begin
(set-mcdr! (q-l q) (mcons i null))
(set-q-l! q (mcdr (q-l q))))))
(define (deq! q)
(begin0
(mcar (q-f q))
(set-q-f! q (mcdr (q-f q)))))
)

@ -1,54 +1,54 @@
(module parser-actions mzscheme
(require "grammar.rkt")
(provide (all-defined-except make-reduce make-reduce*)
(rename make-reduce* make-reduce))
#lang racket/base
(require "grammar.rkt")
(provide (except-out (all-defined-out) make-reduce make-reduce*)
(rename-out [make-reduce* make-reduce]))
;; An action is
;; - (make-shift int)
;; - (make-reduce prod runtime-action)
;; - (make-accept)
;; - (make-goto int)
;; - (no-action)
;; A reduce contains a runtime-reduce so that sharing of the reduces can
;; be easily transferred to sharing of runtime-reduces.
;; An action is
;; - (make-shift int)
;; - (make-reduce prod runtime-action)
;; - (make-accept)
;; - (make-goto int)
;; - (no-action)
;; A reduce contains a runtime-reduce so that sharing of the reduces can
;; be easily transferred to sharing of runtime-reduces.
(define-struct action () (make-inspector))
(define-struct (shift action) (state) (make-inspector))
(define-struct (reduce action) (prod runtime-reduce) (make-inspector))
(define-struct (accept action) () (make-inspector))
(define-struct (goto action) (state) (make-inspector))
(define-struct (no-action action) () (make-inspector))
(define-struct action () #:inspector (make-inspector))
(define-struct (shift action) (state) #:inspector (make-inspector))
(define-struct (reduce action) (prod runtime-reduce) #:inspector (make-inspector))
(define-struct (accept action) () #:inspector (make-inspector))
(define-struct (goto action) (state) #:inspector (make-inspector))
(define-struct (no-action action) () #:inspector (make-inspector))
(define (make-reduce* p)
(make-reduce p
(vector (prod-index p)
(gram-sym-symbol (prod-lhs p))
(vector-length (prod-rhs p)))))
(define (make-reduce* p)
(make-reduce p
(vector (prod-index p)
(gram-sym-symbol (prod-lhs p))
(vector-length (prod-rhs p)))))
;; A runtime-action is
;; non-negative-int (shift)
;; (vector int symbol int) (reduce)
;; 'accept (accept)
;; negative-int (goto)
;; #f (no-action)
;; A runtime-action is
;; non-negative-int (shift)
;; (vector int symbol int) (reduce)
;; 'accept (accept)
;; negative-int (goto)
;; #f (no-action)
(define (action->runtime-action a)
(cond
((shift? a) (shift-state a))
((reduce? a) (reduce-runtime-reduce a))
((accept? a) 'accept)
((goto? a) (- (+ (goto-state a) 1)))
((no-action? a) #f)))
(define (action->runtime-action a)
(cond
[(shift? a) (shift-state a)]
[(reduce? a) (reduce-runtime-reduce a)]
[(accept? a) 'accept]
[(goto? a) (- (+ (goto-state a) 1))]
[(no-action? a) #f]))
(define (runtime-shift? x) (and (integer? x) (>= x 0)))
(define runtime-reduce? vector?)
(define (runtime-accept? x) (eq? x 'accept))
(define (runtime-goto? x) (and (integer? x) (< x 0)))
(define (runtime-shift? x) (and (integer? x) (>= x 0)))
(define runtime-reduce? vector?)
(define (runtime-accept? x) (eq? x 'accept))
(define (runtime-goto? x) (and (integer? x) (< x 0)))
(define runtime-shift-state values)
(define (runtime-reduce-prod-num x) (vector-ref x 0))
(define (runtime-reduce-lhs x) (vector-ref x 1))
(define (runtime-reduce-rhs-length x) (vector-ref x 2))
(define (runtime-goto-state x) (- (+ x 1)))
(define runtime-shift-state values)
(define (runtime-reduce-prod-num x) (vector-ref x 0))
(define (runtime-reduce-lhs x) (vector-ref x 1))
(define (runtime-reduce-rhs-length x) (vector-ref x 2))
(define (runtime-goto-state x) (- (+ x 1)))
)

@ -1,113 +1,103 @@
(module parser-builder mzscheme
#lang racket/base
(require "input-file-parser.rkt"
"grammar.rkt"
"table.rkt"
racket/class
racket/contract)
(require (for-template racket/base))
(require "input-file-parser.rkt"
"grammar.rkt"
"table.rkt"
mzlib/class
racket/contract)
(require-for-template mzscheme)
(provide/contract [build-parser (-> string? any/c any/c
(listof identifier?)
(listof identifier?)
(listof identifier?)
(or/c syntax? #f)
syntax?
(values any/c any/c any/c any/c))])
(provide/contract
(build-parser (-> string? any/c any/c
(listof identifier?)
(listof identifier?)
(listof identifier?)
(or/c syntax? #f)
syntax?
(values any/c any/c any/c any/c))))
;; fix-check-syntax : (listof identifier?) (listof identifier?) (listof identifier?)
;; (union syntax? false/c) syntax?) -> syntax?
(define (fix-check-syntax input-terms start ends assocs prods)
(let* ((term-binders (get-term-list input-terms))
(get-term-binder
(let ((t (make-hash-table)))
(for-each
(lambda (term)
(hash-table-put! t (syntax-e term) term))
term-binders)
(lambda (x)
(let ((r (hash-table-get t (syntax-e x) (lambda () #f))))
(if r
(syntax-local-introduce (datum->syntax-object r (syntax-e x) x x))
x)))))
(rhs-list
(syntax-case prods ()
(((_ rhs ...) ...)
(syntax->list (syntax (rhs ... ...)))))))
(with-syntax (((tmp ...) (map syntax-local-introduce term-binders))
((term-group ...)
(map (lambda (tg)
(syntax-property
(datum->syntax-object tg #f)
'disappeared-use
tg))
input-terms))
((end ...)
(map get-term-binder ends))
((start ...)
(map get-term-binder start))
((bind ...)
(syntax-case prods ()
(((bind _ ...) ...)
(syntax->list (syntax (bind ...))))))
(((bound ...) ...)
(map
(lambda (rhs)
;; fix-check-syntax : (listof identifier?) (listof identifier?) (listof identifier?)
;; (union syntax? false/c) syntax?) -> syntax?
(define (fix-check-syntax input-terms start ends assocs prods)
(define term-binders (get-term-list input-terms))
(define get-term-binder
(let ([t (make-hasheq)])
(for ([term (in-list term-binders)])
(hash-set! t (syntax-e term) term))
(λ (x)
(define r (hash-ref t (syntax-e x) (λ () #f)))
(if r
(syntax-local-introduce (datum->syntax r (syntax-e x) x x))
x))))
(define rhs-list (syntax-case prods ()
[((_ RHS ...) ...) (syntax->list #'(RHS ... ...))]))
(with-syntax ([(TMP ...) (map syntax-local-introduce term-binders)]
[(TERM-GROUP ...)
(map (λ (tg)
(syntax-property
(datum->syntax tg #f)
'disappeared-use
tg))
input-terms)]
[(END ...) (map get-term-binder ends)]
[(START ...) (map get-term-binder start)]
[(BIND ...) (syntax-case prods ()
(((BIND _ ...) ...)
(syntax->list #'(BIND ...))))]
[((BOUND ...) ...)
(map (λ (rhs)
(syntax-case rhs ()
(((bound ...) (_ pbound) __)
[((BOUND ...) (_ PBOUND) __)
(map get-term-binder
(cons (syntax pbound)
(syntax->list (syntax (bound ...))))))
(((bound ...) _)
(cons #'PBOUND (syntax->list #'(BOUND ...))))]
[((BOUND ...) _)
(map get-term-binder
(syntax->list (syntax (bound ...)))))))
rhs-list))
((prec ...)
(if assocs
(map get-term-binder
(syntax-case assocs ()
(((__ term ...) ...)
(syntax->list (syntax (term ... ...))))))
null)))
#`(when #f
(let ((bind void) ... (tmp void) ...)
(void bound ... ... term-group ... start ... end ... prec ...))))))
(require mzlib/list "parser-actions.rkt")
(define (build-parser filename src-pos suppress input-terms start end assocs prods)
(let* ((grammar (parse-input input-terms start end assocs prods src-pos))
(table (build-table grammar filename suppress))
(all-tokens (make-hash-table))
(actions-code
`(vector ,@(map prod-action (send grammar get-prods)))))
(for-each (lambda (term)
(hash-table-put! all-tokens (gram-sym-symbol term) #t))
(send grammar get-terms))
#;(let ((num-states (vector-length table))
(num-gram-syms (+ (send grammar get-num-terms)
(send grammar get-num-non-terms)))
(num-ht-entries (apply + (map length (vector->list table))))
(num-reduces
(let ((ht (make-hash-table)))
(for-each
(lambda (x)
(when (reduce? x)
(hash-table-put! ht x #t)))
(map cdr (apply append (vector->list table))))
(length (hash-table-map ht void)))))
(printf "~a states, ~a grammar symbols, ~a hash-table entries, ~a reduces\n"
num-states num-gram-syms num-ht-entries num-reduces)
(printf "~a -- ~aKB, previously ~aKB\n"
(/ (+ 2 num-states
(* 4 num-states) (* 2 1.5 num-ht-entries)
(* 5 num-reduces)) 256.0)
(/ (+ 2 num-states
(* 4 num-states) (* 2 2.3 num-ht-entries)
(* 5 num-reduces)) 256.0)
(/ (+ 2 (* num-states num-gram-syms) (* 5 num-reduces)) 256.0)))
(values table
all-tokens
actions-code
(fix-check-syntax input-terms start end assocs prods))))
)
(syntax->list #'(BOUND ...)))]))
rhs-list)]
[(PREC ...)
(if assocs
(map get-term-binder
(syntax-case assocs ()
(((__ TERM ...) ...)
(syntax->list #'(TERM ... ...)))))
null)])
#`(when #f
(let ((BIND void) ... (TMP void) ...)
(void BOUND ... ... TERM-GROUP ... START ... END ... PREC ...)))))
(require racket/list "parser-actions.rkt")
(define (build-parser filename src-pos suppress input-terms start end assocs prods)
(define grammar (parse-input input-terms start end assocs prods src-pos))
(define table (build-table grammar filename suppress))
(define all-tokens (make-hasheq))
(define actions-code `(vector ,@(map prod-action (send grammar get-prods))))
(for ([term (in-list (send grammar get-terms))])
(hash-set! all-tokens (gram-sym-symbol term) #t))
#;(let ((num-states (vector-length table))
(num-gram-syms (+ (send grammar get-num-terms)
(send grammar get-num-non-terms)))
(num-ht-entries (apply + (map length (vector->list table))))
(num-reduces
(let ((ht (make-hasheq)))
(for-each
(λ (x)
(when (reduce? x)
(hash-set! ht x #t)))
(map cdr (apply append (vector->list table))))
(length (hash-table-map ht void)))))
(printf "~a states, ~a grammar symbols, ~a hash-table entries, ~a reduces\n"
num-states num-gram-syms num-ht-entries num-reduces)
(printf "~a -- ~aKB, previously ~aKB\n"
(/ (+ 2 num-states
(* 4 num-states) (* 2 1.5 num-ht-entries)
(* 5 num-reduces)) 256.0)
(/ (+ 2 num-states
(* 4 num-states) (* 2 2.3 num-ht-entries)
(* 5 num-reduces)) 256.0)
(/ (+ 2 (* num-states num-gram-syms) (* 5 num-reduces)) 256.0)))
(values table
all-tokens
actions-code
(fix-check-syntax input-terms start end assocs prods)))

@ -1,290 +1,264 @@
#lang scheme/base
#lang racket/base
(require "grammar.rkt"
"lr0.rkt"
"lalr.rkt"
"parser-actions.rkt"
racket/contract
racket/list
racket/class)
;; Routine to build the LALR table
;; Routine to build the LALR table
(require "grammar.rkt"
"lr0.rkt"
"lalr.rkt"
"parser-actions.rkt"
racket/contract
mzlib/list
mzlib/class)
(define (is-a-grammar%? x) (is-a? x grammar%))
(provide/contract
(build-table (-> is-a-grammar%? string? any/c
(vectorof (listof (cons/c (or/c term? non-term?) action?))))))
(define (is-a-grammar%? x) (is-a? x grammar%))
(provide/contract
(build-table (-> is-a-grammar%? string? any/c
(vectorof (listof (cons/c (or/c term? non-term?) action?))))))
;; A parse-table is (vectorof (listof (cons/c gram-sym? action)))
;; A grouped-parse-table is (vectorof (listof (cons/c gram-sym? (listof action))))
;; A parse-table is (vectorof (listof (cons/c gram-sym? action)))
;; A grouped-parse-table is (vectorof (listof (cons/c gram-sym? (listof action))))
;; make-parse-table : int -> parse-table
(define (make-parse-table num-states)
(make-vector num-states null))
;; make-parse-table : int -> parse-table
(define (make-parse-table num-states)
(make-vector num-states null))
;; table-add!: parse-table nat symbol action ->
(define (table-add! table state-index symbol val)
(vector-set! table state-index (cons (cons symbol val)
(vector-ref table state-index))))
;; table-add!: parse-table nat symbol action ->
(define (table-add! table state-index symbol val)
(vector-set! table state-index (cons (cons symbol val)
(vector-ref table state-index))))
;; group-table : parse-table -> grouped-parse-table
(define (group-table table)
(list->vector
(map
(lambda (state-entry)
(let ((ht (make-hash)))
(for-each
(lambda (gs/actions)
(let ((group (hash-ref ht (car gs/actions) (lambda () null))))
(unless (member (cdr gs/actions) group)
(hash-set! ht (car gs/actions) (cons (cdr gs/actions) group)))))
state-entry)
(hash-map ht cons)))
(vector->list table))))
;; group-table : parse-table -> grouped-parse-table
(define (group-table table)
(list->vector
(for/list ([state-entry (in-list (vector->list table))])
(define ht (make-hasheq))
(for* ([gs/actions (in-list state-entry)]
[group (in-value (hash-ref ht (car gs/actions) (λ () null)))]
#:unless (member (cdr gs/actions) group))
(hash-set! ht (car gs/actions) (cons (cdr gs/actions) group)))
(hash-map ht cons))))
;; table-map : (vectorof (listof (cons/c gram-sym? X))) (gram-sym? X -> Y) ->
;; (vectorof (listof (cons/c gram-sym? Y)))
(define (table-map f table)
(list->vector
(map
(lambda (state-entry)
(map
(lambda (gs/X)
(cons (car gs/X) (f (car gs/X) (cdr gs/X))))
state-entry))
(vector->list table))))
;; table-map : (vectorof (listof (cons/c gram-sym? X))) (gram-sym? X -> Y) ->
;; (vectorof (listof (cons/c gram-sym? Y)))
(define (table-map f table)
(list->vector
(for/list ([state-entry (in-list (vector->list table))])
(for/list ([gs/X (in-list state-entry)])
(cons (car gs/X) (f (car gs/X) (cdr gs/X)))))))
(define (bit-vector-for-each f bv)
(letrec ((for-each
(lambda (bv number)
(cond
((= 0 bv) (void))
((= 1 (bitwise-and 1 bv))
(f number)
(for-each (arithmetic-shift bv -1) (add1 number)))
(else (for-each (arithmetic-shift bv -1) (add1 number)))))))
(for-each bv 0)))
(define (bit-vector-for-each f bv)
(let loop ([bv bv] [number 0])
(cond
[(zero? bv) (void)]
[(= 1 (bitwise-and 1 bv))
(f number)
(loop (arithmetic-shift bv -1) (add1 number))]
[else (loop (arithmetic-shift bv -1) (add1 number))])))
;; print-entry: symbol action output-port ->
;; prints the action a for lookahead sym to the given port
(define (print-entry sym a port)
(let ((s "\t~a\t\t\t\t\t~a\t~a\n"))
(cond
((shift? a)
(fprintf port s sym "shift" (shift-state a)))
((reduce? a)
(fprintf port s sym "reduce" (prod-index (reduce-prod a))))
((accept? a)
(fprintf port s sym "accept" ""))
((goto? a)
(fprintf port s sym "goto" (goto-state a))))))
;; print-entry: symbol action output-port ->
;; prints the action a for lookahead sym to the given port
(define (print-entry sym a port)
(define s "\t~a\t\t\t\t\t~a\t~a\n")
(cond
[(shift? a) (fprintf port s sym "shift" (shift-state a))]
[(reduce? a) (fprintf port s sym "reduce" (prod-index (reduce-prod a)))]
[(accept? a) (fprintf port s sym "accept" "")]
[(goto? a) (fprintf port s sym "goto" (goto-state a))]))
;; count: ('a -> bool) * 'a list -> num
;; counts the number of elements in list that satisfy pred
(define (count pred list)
(cond
((null? list) 0)
((pred (car list)) (+ 1 (count pred (cdr list))))
(else (count pred (cdr list)))))
;; count: ('a -> bool) * 'a list -> num
;; counts the number of elements in list that satisfy pred
(define (count pred list)
(cond
[(null? list) 0]
[(pred (car list)) (+ 1 (count pred (cdr list)))]
[else (count pred (cdr list))]))
;; display-parser: LR0-automaton grouped-parse-table (listof prod?) output-port ->
;; Prints out the parser given by table.
(define (display-parser a grouped-table prods port)
(let* ((SR-conflicts 0)
(RR-conflicts 0))
(for-each
(lambda (prod)
(fprintf port
"~a\t~a\t=\t~a\n"
(prod-index prod)
(gram-sym-symbol (prod-lhs prod))
(map gram-sym-symbol (vector->list (prod-rhs prod)))))
prods)
(send a for-each-state
(lambda (state)
;; display-parser: LR0-automaton grouped-parse-table (listof prod?) output-port ->
;; Prints out the parser given by table.
(define (display-parser a grouped-table prods port)
(define SR-conflicts 0)
(define RR-conflicts 0)
(for ([prod (in-list prods)])
(fprintf port
"~a\t~a\t=\t~a\n"
(prod-index prod)
(gram-sym-symbol (prod-lhs prod))
(map gram-sym-symbol (vector->list (prod-rhs prod)))))
(send a for-each-state
(λ (state)
(fprintf port "State ~a\n" (kernel-index state))
(for-each (lambda (item)
(fprintf port "\t~a\n" (item->string item)))
(kernel-items state))
(for ([item (in-list (kernel-items state))])
(fprintf port "\t~a\n" (item->string item)))
(newline port)
(for-each
(lambda (gs/action)
(let ((sym (gram-sym-symbol (car gs/action)))
(act (cdr gs/action)))
(cond
((null? act) (void))
((null? (cdr act))
(print-entry sym (car act) port))
(else
(fprintf port "begin conflict:\n")
(when (> (count reduce? act) 1)
(set! RR-conflicts (add1 RR-conflicts)))
(when (> (count shift? act) 0)
(set! SR-conflicts (add1 SR-conflicts)))
(map (lambda (x) (print-entry sym x port)) act)
(fprintf port "end conflict\n")))))
(vector-ref grouped-table (kernel-index state)))
(for ([gs/action (in-list (vector-ref grouped-table (kernel-index state)))])
(define sym (gram-sym-symbol (car gs/action)))
(define act (cdr gs/action))
(cond
[(null? act) (void)]
[(null? (cdr act))
(print-entry sym (car act) port)]
[else
(fprintf port "begin conflict:\n")
(when (> (count reduce? act) 1)
(set! RR-conflicts (add1 RR-conflicts)))
(when (> (count shift? act) 0)
(set! SR-conflicts (add1 SR-conflicts)))
(map (λ (x) (print-entry sym x port)) act)
(fprintf port "end conflict\n")]))
(newline port)))
(when (> SR-conflicts 0)
(fprintf port "~a shift/reduce conflict~a\n"
SR-conflicts
(if (= SR-conflicts 1) "" "s")))
(when (> RR-conflicts 0)
(fprintf port "~a reduce/reduce conflict~a\n"
RR-conflicts
(if (= RR-conflicts 1) "" "s")))))
(when (> SR-conflicts 0)
(fprintf port "~a shift/reduce conflict~a\n"
SR-conflicts
(if (= SR-conflicts 1) "" "s")))
(when (> RR-conflicts 0)
(fprintf port "~a reduce/reduce conflict~a\n"
RR-conflicts
(if (= RR-conflicts 1) "" "s"))))
;; resolve-conflict : (listof action?) -> action? bool bool
(define (resolve-conflict actions)
(cond
((null? actions) (values (make-no-action) #f #f))
((null? (cdr actions))
(values (car actions) #f #f))
(else
(let ((SR-conflict? (> (count shift? actions) 0))
(RR-conflict? (> (count reduce? actions) 1)))
(let loop ((current-guess #f)
(rest actions))
(cond
((null? rest) (values current-guess SR-conflict? RR-conflict?))
((shift? (car rest)) (values (car rest) SR-conflict? RR-conflict?))
((not current-guess)
(loop (car rest) (cdr rest)))
((and (reduce? (car rest))
(< (prod-index (reduce-prod (car rest)))
(prod-index (reduce-prod current-guess))))
(loop (car rest) (cdr rest)))
((accept? (car rest))
(eprintf "accept/reduce or accept/shift conflicts. Check the grammar for useless cycles of productions\n")
(loop current-guess (cdr rest)))
(else (loop current-guess (cdr rest)))))))))
;; resolve-conflict : (listof action?) -> action? bool bool
(define (resolve-conflict actions)
(cond
[(null? actions) (values (make-no-action) #f #f)]
[(null? (cdr actions)) (values (car actions) #f #f)]
[else
(define SR-conflict? (> (count shift? actions) 0))
(define RR-conflict? (> (count reduce? actions) 1))
(let loop ((current-guess #f)
(rest actions))
(cond
[(null? rest) (values current-guess SR-conflict? RR-conflict?)]
[(shift? (car rest)) (values (car rest) SR-conflict? RR-conflict?)]
[(not current-guess) (loop (car rest) (cdr rest))]
[(and (reduce? (car rest))
(< (prod-index (reduce-prod (car rest)))
(prod-index (reduce-prod current-guess))))
(loop (car rest) (cdr rest))]
[(accept? (car rest))
(eprintf "accept/reduce or accept/shift conflicts. Check the grammar for useless cycles of productions\n")
(loop current-guess (cdr rest))]
[else (loop current-guess (cdr rest))]))]))
;; resolve-conflicts : grouped-parse-table bool -> parse-table
(define (resolve-conflicts grouped-table suppress)
(let* ((SR-conflicts 0)
(RR-conflicts 0)
(table (table-map
(lambda (gs actions)
(let-values (((action SR? RR?)
(resolve-conflict actions)))
(when SR?
(set! SR-conflicts (add1 SR-conflicts)))
(when RR?
(set! RR-conflicts (add1 RR-conflicts)))
action))
grouped-table)))
(unless suppress
(when (> SR-conflicts 0)
(eprintf "~a shift/reduce conflict~a\n"
SR-conflicts
(if (= SR-conflicts 1) "" "s")))
(when (> RR-conflicts 0)
(eprintf "~a reduce/reduce conflict~a\n"
RR-conflicts
(if (= RR-conflicts 1) "" "s"))))
table))
;; resolve-conflicts : grouped-parse-table bool -> parse-table
(define (resolve-conflicts grouped-table suppress)
(define SR-conflicts 0)
(define RR-conflicts 0)
(define table (table-map
(λ (gs actions)
(let-values ([(action SR? RR?)
(resolve-conflict actions)])
(when SR?
(set! SR-conflicts (add1 SR-conflicts)))
(when RR?
(set! RR-conflicts (add1 RR-conflicts)))
action))
grouped-table))
(unless suppress
(when (> SR-conflicts 0)
(eprintf "~a shift/reduce conflict~a\n"
SR-conflicts
(if (= SR-conflicts 1) "" "s")))
(when (> RR-conflicts 0)
(eprintf "~a reduce/reduce conflict~a\n"
RR-conflicts
(if (= RR-conflicts 1) "" "s"))))
table)
;; resolve-sr-conflict : (listof action) (union int #f) -> (listof action)
;; Resolves a single shift-reduce conflict, if precedences are in place.
(define (resolve-sr-conflict/prec actions shift-prec)
(let* ((shift (if (shift? (car actions))
(car actions)
(cadr actions)))
(reduce (if (shift? (car actions))
(cadr actions)
(car actions)))
(reduce-prec (prod-prec (reduce-prod reduce))))
(cond
((and shift-prec reduce-prec)
(cond
((< (prec-num shift-prec) (prec-num reduce-prec))
(list reduce))
((> (prec-num shift-prec) (prec-num reduce-prec))
(list shift))
((eq? 'left (prec-assoc shift-prec))
(list reduce))
((eq? 'right (prec-assoc shift-prec))
(list shift))
(else null)))
(else actions))))
;; resolve-sr-conflict : (listof action) (union int #f) -> (listof action)
;; Resolves a single shift-reduce conflict, if precedences are in place.
(define (resolve-sr-conflict/prec actions shift-prec)
(define shift (if (shift? (car actions))
(car actions)
(cadr actions)))
(define reduce (if (shift? (car actions))
(cadr actions)
(car actions)))
(define reduce-prec (prod-prec (reduce-prod reduce)))
(cond
[(and shift-prec reduce-prec)
(cond
[(< (prec-num shift-prec) (prec-num reduce-prec))
(list reduce)]
[(> (prec-num shift-prec) (prec-num reduce-prec))
(list shift)]
[(eq? 'left (prec-assoc shift-prec))
(list reduce)]
[(eq? 'right (prec-assoc shift-prec))
(list shift)]
[else null])]
[else actions]))
;; resolve-prec-conflicts : parse-table -> grouped-parse-table
(define (resolve-prec-conflicts table)
(table-map
(lambda (gs actions)
(cond
((and (term? gs)
(= 2 (length actions))
(or (shift? (car actions))
(shift? (cadr actions))))
(resolve-sr-conflict/prec actions (term-prec gs)))
(else actions)))
(group-table table)))
;; resolve-prec-conflicts : parse-table -> grouped-parse-table
(define (resolve-prec-conflicts table)
(table-map
(λ (gs actions)
(cond
[(and (term? gs)
(= 2 (length actions))
(or (shift? (car actions))
(shift? (cadr actions))))
(resolve-sr-conflict/prec actions (term-prec gs))]
[else actions]))
(group-table table)))
;; build-table: grammar string bool -> parse-table
(define (build-table g file suppress)
(let* ((a (build-lr0-automaton g))
(term-vector (list->vector (send g get-terms)))
(end-terms (send g get-end-terms))
(table (make-parse-table (send a get-num-states)))
(get-lookahead (compute-LA a g))
(reduce-cache (make-hash)))
;; build-table: grammar string bool -> parse-table
(define (build-table g file suppress)
(define a (build-lr0-automaton g))
(define term-vector (list->vector (send g get-terms)))
(define end-terms (send g get-end-terms))
(define table (make-parse-table (send a get-num-states)))
(define get-lookahead (compute-LA a g))
(define reduce-cache (make-hash))
(for ([trans-key/state (in-list (send a get-transitions))])
(define from-state-index (kernel-index (trans-key-st (car trans-key/state))))
(define gs (trans-key-gs (car trans-key/state)))
(define to-state (cdr trans-key/state))
(table-add! table from-state-index gs
(cond
((non-term? gs)
(make-goto (kernel-index to-state)))
((member gs end-terms)
(make-accept))
(else
(make-shift
(kernel-index to-state))))))
(send a for-each-state
(λ (state)
(for ([item (in-list (append (hash-ref (send a get-epsilon-trans) state (λ () null))
(filter (λ (item)
(not (move-dot-right item)))
(kernel-items state))))])
(let ([item-prod (item-prod item)])
(bit-vector-for-each
(λ (term-index)
(unless (start-item? item)
(let ((r (hash-ref reduce-cache item-prod
(λ ()
(let ((r (make-reduce item-prod)))
(hash-set! reduce-cache item-prod r)
r)))))
(table-add! table
(kernel-index state)
(vector-ref term-vector term-index)
r))))
(get-lookahead state item-prod))))))
(for-each
(lambda (trans-key/state)
(let ((from-state-index (kernel-index (trans-key-st (car trans-key/state))))
(gs (trans-key-gs (car trans-key/state)))
(to-state (cdr trans-key/state)))
(table-add! table from-state-index gs
(cond
((non-term? gs)
(make-goto (kernel-index to-state)))
((member gs end-terms)
(make-accept))
(else
(make-shift
(kernel-index to-state)))))))
(send a get-transitions))
(send a for-each-state
(lambda (state)
(for-each
(lambda (item)
(let ((item-prod (item-prod item)))
(bit-vector-for-each
(lambda (term-index)
(unless (start-item? item)
(let ((r (hash-ref reduce-cache item-prod
(lambda ()
(let ((r (make-reduce item-prod)))
(hash-set! reduce-cache item-prod r)
r)))))
(table-add! table
(kernel-index state)
(vector-ref term-vector term-index)
r))))
(get-lookahead state item-prod))))
(append (hash-ref (send a get-epsilon-trans) state (lambda () null))
(filter (lambda (item)
(not (move-dot-right item)))
(kernel-items state))))))
(let ((grouped-table (resolve-prec-conflicts table)))
(unless (string=? file "")
(with-handlers [(exn:fail:filesystem?
(lambda (e)
(eprintf
"Cannot write debug output to file \"~a\": ~a\n"
file
(exn-message e))))]
(call-with-output-file file
(lambda (port)
(display-parser a grouped-table (send g get-prods) port))
#:exists 'truncate)))
(resolve-conflicts grouped-table suppress))))
(define grouped-table (resolve-prec-conflicts table))
(unless (string=? file "")
(with-handlers [(exn:fail:filesystem?
(λ (e)
(eprintf
"Cannot write debug output to file \"~a\": ~a\n"
file
(exn-message e))))]
(call-with-output-file file
(λ (port)
(display-parser a grouped-table (send g get-prods) port))
#:exists 'truncate)))
(resolve-conflicts grouped-table suppress))

@ -1,118 +1,71 @@
(module yacc-helper mzscheme
#lang racket/base
(require (prefix-in rl: racket/list)
"../private-lex/token-syntax.rkt")
(require mzlib/list
"../private-lex/token-syntax.rkt")
;; General helper routines
(provide duplicate-list? remove-duplicates overlap? vector-andmap display-yacc)
(define (vector-andmap pred vec)
(for/and ([item (in-vector vec)])
(pred vec)))
;; General helper routines
(provide duplicate-list? remove-duplicates overlap? vector-andmap display-yacc)
(define (vector-andmap f v)
(let loop ((i 0))
(cond
((= i (vector-length v)) #t)
(else (if (f (vector-ref v i))
(loop (add1 i))
#f)))))
;; duplicate-list?: symbol list -> #f | symbol
;; returns a symbol that exists twice in l, or false if no such symbol
;; exists
(define (duplicate-list? syms)
(rl:check-duplicates syms eq?))
;; duplicate-list?: symbol list -> #f | symbol
;; returns a symbol that exists twice in l, or false if no such symbol
;; exists
(define (duplicate-list? l)
(letrec ((t (make-hash-table))
(dl? (lambda (l)
(cond
((null? l) #f)
((hash-table-get t (car l) (lambda () #f)) =>
(lambda (x) x))
(else
(hash-table-put! t (car l) (car l))
(dl? (cdr l)))))))
(dl? l)))
;; remove-duplicates: syntax-object list -> syntax-object list
;; removes the duplicates from the lists
(define (remove-duplicates syms)
(rl:remove-duplicates syms equal? #:key syntax->datum))
;; remove-duplicates: syntax-object list -> syntax-object list
;; removes the duplicates from the lists
(define (remove-duplicates sl)
(let ((t (make-hash-table)))
(letrec ((x
(lambda (sl)
(cond
((null? sl) sl)
((hash-table-get t (syntax-object->datum (car sl)) (lambda () #f))
(x (cdr sl)))
(else
(hash-table-put! t (syntax-object->datum (car sl)) #t)
(cons (car sl) (x (cdr sl))))))))
(x sl))))
;; overlap?: symbol list * symbol list -> #f | symbol
;; Returns an symbol in l1 intersect l2, or #f is no such symbol exists
(define (overlap? l1 l2)
(let/ec ret
(let ((t (make-hash-table)))
(for-each (lambda (s1)
(hash-table-put! t s1 s1))
l1)
(for-each (lambda (s2)
(cond
((hash-table-get t s2 (lambda () #f)) =>
(lambda (o) (ret o)))))
l2)
#f)))
;; overlap?: symbol list * symbol list -> #f | symbol
;; Returns an symbol in l1 intersect l2, or #f is no such symbol exists
(define (overlap? syms1 syms2)
(for/first ([sym1 (in-list syms1)]
#:when (memq sym1 syms2))
sym1))
(define (display-yacc grammar tokens start precs port)
(let-syntax ((p (syntax-rules ()
((_ args ...) (fprintf port args ...)))))
(let* ((tokens (map syntax-local-value tokens))
(eterms (filter e-terminals-def? tokens))
(terms (filter terminals-def? tokens))
(term-table (make-hash-table))
(display-rhs
(lambda (rhs)
(for-each (lambda (sym) (p "~a " (hash-table-get term-table sym (lambda () sym))))
(car rhs))
(if (= 3 (length rhs))
(p "%prec ~a" (cadadr rhs)))
(p "\n"))))
(for-each
(lambda (t)
(for-each
(lambda (t)
(hash-table-put! term-table t (format "'~a'" t)))
(syntax-object->datum (e-terminals-def-t t))))
eterms)
(for-each
(lambda (t)
(for-each
(lambda (t)
(p "%token ~a\n" t)
(hash-table-put! term-table t (format "~a" t)))
(syntax-object->datum (terminals-def-t t))))
terms)
(if precs
(for-each (lambda (prec)
(p "%~a " (car prec))
(for-each (lambda (tok)
(p " ~a" (hash-table-get term-table tok)))
(cdr prec))
(p "\n"))
precs))
(p "%start ~a\n" start)
(p "%%\n")
(define (display-yacc grammar tokens start precs port)
(let-syntax ([p (syntax-rules ()
((_ args ...) (fprintf port args ...)))])
(let* ([tokens (map syntax-local-value tokens)]
[eterms (filter e-terminals-def? tokens)]
[terms (filter terminals-def? tokens)]
[term-table (make-hasheq)]
[display-rhs
(λ (rhs)
(for ([sym (in-list (car rhs))])
(p "~a " (hash-ref term-table sym (λ () sym))))
(when (= 3 (length rhs))
(p "%prec ~a" (cadadr rhs)))
(p "\n"))])
(for* ([t (in-list eterms)]
[t (in-list (syntax->datum (e-terminals-def-t t)))])
(hash-set! term-table t (format "'~a'" t)))
(for* ([t (in-list terms)]
[t (in-list (syntax->datum (terminals-def-t t)))])
(p "%token ~a\n" t)
(hash-set! term-table t (format "~a" t)))
(when precs
(for ([prec (in-list precs)])
(p "%~a " (car prec))
(for ([tok (in-list (cdr prec))])
(p " ~a" (hash-ref term-table tok)))
(p "\n")))
(p "%start ~a\n" start)
(p "%%\n")
(for ([prod (in-list grammar)])
(define nt (car prod))
(p "~a: " nt)
(display-rhs (cadr prod))
(for ([rhs (in-list (cddr prod))])
(p "| ")
(display-rhs rhs))
(p ";\n"))
(p "%%\n"))))
(for-each (lambda (prod)
(let ((nt (car prod)))
(p "~a: " nt)
(display-rhs (cadr prod))
(for-each (lambda (rhs)
(p "| ")
(display-rhs rhs))
(cddr prod))
(p ";\n")))
grammar)
(p "%%\n"))))
)

@ -1,135 +1,130 @@
(module yacc-to-scheme mzscheme
(require br-parser-tools/lex
(prefix : br-parser-tools/lex-sre)
br-parser-tools/yacc
syntax/readerr
mzlib/list)
(provide trans)
#lang racket/base
(require br-parser-tools/lex
(prefix-in : br-parser-tools/lex-sre)
br-parser-tools/yacc
syntax/readerr
racket/list)
(provide trans)
(define match-double-string
(lexer
((:+ (:~ #\" #\\)) (append (string->list lexeme)
(match-double-string input-port)))
((:: #\\ any-char) (cons (string-ref lexeme 1) (match-double-string input-port)))
(#\" null)))
(define match-double-string
(lexer
[(:+ (:~ #\" #\\)) (append (string->list lexeme)
(match-double-string input-port))]
[(:: #\\ any-char) (cons (string-ref lexeme 1) (match-double-string input-port))]
[#\" null]))
(define match-single-string
(lexer
((:+ (:~ #\' #\\)) (append (string->list lexeme)
(match-single-string input-port)))
((:: #\\ any-char) (cons (string-ref lexeme 1) (match-single-string input-port)))
(#\' null)))
(define match-single-string
(lexer
[(:+ (:~ #\' #\\)) (append (string->list lexeme)
(match-single-string input-port))]
[(:: #\\ any-char) (cons (string-ref lexeme 1) (match-single-string input-port))]
[#\' null]))
(define-lex-abbrevs
(letter (:or (:/ "a" "z") (:/ "A" "Z")))
(digit (:/ "0" "9"))
(initial (:or letter (char-set "!$%&*/<=>?^_~@")))
(subsequent (:or initial digit (char-set "+-.@")))
(comment (:: "/*" (complement (:: any-string "*/" any-string)) "*/")))
(define-lex-abbrevs
[letter (:or (:/ "a" "z") (:/ "A" "Z"))]
[digit (:/ "0" "9")]
[initial (:or letter (char-set "!$%&*/<=>?^_~@"))]
[subsequent (:or initial digit (char-set "+-.@"))]
[comment (:: "/*" (complement (:: any-string "*/" any-string)) "*/")])
(define-empty-tokens x
(EOF PIPE |:| SEMI |%%| %prec))
(define-tokens y
(SYM STRING))
(define-empty-tokens x (EOF PIPE |:| SEMI |%%| %prec))
(define-tokens y (SYM STRING))
(define get-token-grammar
(lexer-src-pos
("%%" '|%%|)
(":" (string->symbol lexeme))
("%prec" (string->symbol lexeme))
(#\| 'PIPE)
((:+ (:or #\newline #\tab " " comment (:: "{" (:* (:~ "}")) "}")))
(return-without-pos (get-token-grammar input-port)))
(#\; 'SEMI)
(#\' (token-STRING (string->symbol (list->string (match-single-string input-port)))))
(#\" (token-STRING (string->symbol (list->string (match-double-string input-port)))))
((:: initial (:* subsequent)) (token-SYM (string->symbol lexeme)))))
(define get-token-grammar
(lexer-src-pos
["%%" '|%%|]
[":" (string->symbol lexeme)]
["%prec" (string->symbol lexeme)]
[#\| 'PIPE]
[(:+ (:or #\newline #\tab " " comment (:: "{" (:* (:~ "}")) "}")))
(return-without-pos (get-token-grammar input-port))]
[#\; 'SEMI]
[#\' (token-STRING (string->symbol (list->string (match-single-string input-port))))]
[#\" (token-STRING (string->symbol (list->string (match-double-string input-port))))]
[(:: initial (:* subsequent)) (token-SYM (string->symbol lexeme))]))
(define (parse-grammar enter-term enter-empty-term enter-non-term)
(parser
(tokens x y)
(src-pos)
(error (lambda (tok-ok tok-name tok-value start-pos end-pos)
(raise-read-error
(format "Error Parsing YACC grammar at token: ~a with value: ~a" tok-name tok-value)
(file-path)
(position-line start-pos)
(position-col start-pos)
(position-offset start-pos)
(- (position-offset end-pos) (position-offset start-pos)))))
(define (parse-grammar enter-term enter-empty-term enter-non-term)
(parser
(tokens x y)
(src-pos)
(error (λ (tok-ok tok-name tok-value start-pos end-pos)
(raise-read-error
(format "Error Parsing YACC grammar at token: ~a with value: ~a" tok-name tok-value)
(file-path)
(position-line start-pos)
(position-col start-pos)
(position-offset start-pos)
(- (position-offset end-pos) (position-offset start-pos)))))
(end |%%|)
(start gram)
(grammar
(gram
((production) (list $1))
((production gram) (cons $1 $2)))
(production
((SYM |:| prods SEMI)
(begin
(enter-non-term $1)
(cons $1 $3))))
(prods
((rhs) (list `(,$1 #f)))
((rhs prec) (list `(,$1 ,$2 #f)))
((rhs PIPE prods) (cons `(,$1 #f) $3))
((rhs prec PIPE prods) (cons `(,$1 ,$2 #f) $4)))
(prec
((%prec SYM)
(begin
(enter-term $2)
(list 'prec $2)))
((%prec STRING)
(begin
(enter-empty-term $2)
(list 'prec $2))))
(rhs
(() null)
((SYM rhs)
(begin
(enter-term $1)
(cons $1 $2)))
((STRING rhs)
(begin
(enter-empty-term $1)
(cons $1 $2)))))))
(end |%%|)
(start gram)
(grammar
(gram
((production) (list $1))
((production gram) (cons $1 $2)))
(production
((SYM |:| prods SEMI)
(begin
(enter-non-term $1)
(cons $1 $3))))
(prods
((rhs) (list `(,$1 #f)))
((rhs prec) (list `(,$1 ,$2 #f)))
((rhs PIPE prods) (cons `(,$1 #f) $3))
((rhs prec PIPE prods) (cons `(,$1 ,$2 #f) $4)))
(prec
((%prec SYM)
(begin
(enter-term $2)
(list 'prec $2)))
((%prec STRING)
(begin
(enter-empty-term $2)
(list 'prec $2))))
(rhs
(() null)
((SYM rhs)
(begin
(enter-term $1)
(cons $1 $2)))
((STRING rhs)
(begin
(enter-empty-term $1)
(cons $1 $2)))))))
(define (symbol<? a b)
(string<? (symbol->string a) (symbol->string b)))
(define (symbol<? a b)
(string<? (symbol->string a) (symbol->string b)))
(define (trans filename)
(let* ((i (open-input-file filename))
(terms (make-hash-table))
(eterms (make-hash-table))
(nterms (make-hash-table))
(enter-term
(lambda (s)
(if (not (hash-table-get nterms s (lambda () #f)))
(hash-table-put! terms s #t))))
(enter-empty-term
(lambda (s)
(if (not (hash-table-get nterms s (lambda () #f)))
(hash-table-put! eterms s #t))))
(enter-non-term
(lambda (s)
(hash-table-remove! terms s)
(hash-table-remove! eterms s)
(hash-table-put! nterms s #t))))
(port-count-lines! i)
(file-path filename)
(regexp-match "%%" i)
(begin0
(let ((gram ((parse-grammar enter-term enter-empty-term enter-non-term)
(lambda ()
(let ((t (get-token-grammar i)))
t)))))
`(begin
(define-tokens t ,(sort (hash-table-map terms (lambda (k v) k)) symbol<?))
(define-empty-tokens et ,(sort (hash-table-map eterms (lambda (k v) k)) symbol<?))
(parser
(start ___)
(end ___)
(error ___)
(tokens t et)
(grammar ,@gram))))
(close-input-port i)))))
(define (trans filename)
(define i (open-input-file filename))
(define terms (make-hasheq))
(define eterms (make-hasheq))
(define nterms (make-hasheq))
(define (enter-term s)
(when (not (hash-ref nterms s (λ () #f)))
(hash-set! terms s #t)))
(define (enter-empty-term s)
(when (not (hash-ref nterms s (λ () #f)))
(hash-set! eterms s #t)))
(define (enter-non-term s)
(hash-remove! terms s)
(hash-remove! eterms s)
(hash-set! nterms s #t))
(port-count-lines! i)
(file-path filename)
(regexp-match "%%" i)
(begin0
(let ([gram ((parse-grammar enter-term enter-empty-term enter-non-term)
(λ ()
(let ((t (get-token-grammar i)))
t)))])
`(begin
(define-tokens t ,(sort (hash-map terms (λ (k v) k)) symbol<?))
(define-empty-tokens et ,(sort (hash-map eterms (λ (k v) k)) symbol<?))
(parser
(start ___)
(end ___)
(error ___)
(tokens t et)
(grammar ,@gram))))
(close-input-port i)))

@ -1,14 +1,13 @@
#lang scheme/base
(require (for-syntax scheme/base
#lang racket/base
(require (for-syntax racket/base
"private-yacc/parser-builder.rkt"
"private-yacc/grammar.rkt"
"private-yacc/yacc-helper.rkt"
"private-yacc/parser-actions.rkt"))
(require "private-lex/token.rkt"
"private-yacc/parser-actions.rkt")
"private-lex/token.rkt"
"private-yacc/parser-actions.rkt"
mzlib/etc
mzlib/pretty
racket/local
racket/pretty
syntax/readerr)
(provide parser)
@ -17,139 +16,93 @@
;; convert-parse-table : (vectorof (listof (cons/c gram-sym? action?))) ->
;; (vectorof (symbol runtime-action hashtable))
(define-for-syntax (convert-parse-table table)
(list->vector
(map
(lambda (state-entry)
(let ((ht (make-hasheq)))
(for-each
(lambda (gs/action)
(hash-set! ht
(gram-sym-symbol (car gs/action))
(action->runtime-action (cdr gs/action))))
state-entry)
ht))
(vector->list table))))
(for/vector ([state-entry (in-vector table)])
(let ([ht (make-hasheq)])
(for ([gs/action (in-list state-entry)])
(hash-set! ht
(gram-sym-symbol (car gs/action))
(action->runtime-action (cdr gs/action))))
ht)))
(define-syntax (parser stx)
(syntax-case stx ()
((_ args ...)
(let ((arg-list (syntax->list (syntax (args ...))))
(src-pos #f)
(debug #f)
(error #f)
(tokens #f)
(start #f)
(end #f)
(precs #f)
(suppress #f)
(grammar #f)
(yacc-output #f))
(for-each
(lambda (arg)
(syntax-case* arg (debug error tokens start end precs grammar
suppress src-pos yacc-output)
(lambda (a b)
(eq? (syntax-e a) (syntax-e b)))
((debug filename)
(cond
((not (string? (syntax-e (syntax filename))))
(raise-syntax-error
#f
"Debugging filename must be a string"
stx
(syntax filename)))
(debug
(raise-syntax-error #f "Multiple debug declarations" stx))
(else
(set! debug (syntax-e (syntax filename))))))
((suppress)
(set! suppress #t))
((src-pos)
(set! src-pos #t))
((error expression)
(if error
(raise-syntax-error #f "Multiple error declarations" stx)
(set! error (syntax expression))))
((tokens def ...)
(begin
(when tokens
(raise-syntax-error #f "Multiple tokens declarations" stx))
(let ((defs (syntax->list (syntax (def ...)))))
(for-each
(lambda (d)
(unless (identifier? d)
(raise-syntax-error
#f
"Token-group name must be an identifier"
stx
d)))
defs)
(set! tokens defs))))
((start symbol ...)
(let ((symbols (syntax->list (syntax (symbol ...)))))
(for-each
(lambda (sym)
(unless (identifier? sym)
(raise-syntax-error #f
"Start symbol must be a symbol"
stx
sym)))
symbols)
(when start
(raise-syntax-error #f "Multiple start declarations" stx))
(when (null? symbols)
(raise-syntax-error #f
"Missing start symbol"
stx
arg))
(set! start symbols)))
((end symbols ...)
(let ((symbols (syntax->list (syntax (symbols ...)))))
(for-each
(lambda (sym)
(unless (identifier? sym)
(raise-syntax-error #f
"End token must be a symbol"
stx
sym)))
symbols)
(let ((d (duplicate-list? (map syntax-e symbols))))
(when d
(raise-syntax-error
#f
(format "Duplicate end token definition for ~a" d)
stx
arg))
(when (null? symbols)
(raise-syntax-error
#f
"end declaration must contain at least 1 token"
stx
arg))
(when end
(raise-syntax-error #f "Multiple end declarations" stx))
(set! end symbols))))
((precs decls ...)
(if precs
(raise-syntax-error #f "Multiple precs declarations" stx)
(set! precs (syntax/loc arg (decls ...)))))
((grammar prods ...)
(if grammar
(raise-syntax-error #f "Multiple grammar declarations" stx)
(set! grammar (syntax/loc arg (prods ...)))))
((yacc-output filename)
(cond
((not (string? (syntax-e (syntax filename))))
(raise-syntax-error #f
"Yacc-output filename must be a string"
stx
(syntax filename)))
(yacc-output
(raise-syntax-error #f "Multiple yacc-output declarations" stx))
(else
(set! yacc-output (syntax-e (syntax filename))))))
(_ (raise-syntax-error #f "argument must match (debug filename), (error expression), (tokens def ...), (start non-term), (end tokens ...), (precs decls ...), or (grammar prods ...)" stx arg))))
(syntax->list (syntax (args ...))))
[(_ ARGS ...)
(let ([arg-list (syntax->list #'(ARGS ...))]
[src-pos #f]
[debug #f]
[error #f]
[tokens #f]
[start #f]
[end #f]
[precs #f]
[suppress #f]
[grammar #f]
[yacc-output #f])
(for ([arg (in-list (syntax->list #'(ARGS ...)))])
(syntax-case* arg (debug error tokens start end precs grammar
suppress src-pos yacc-output)
(λ (a b) (eq? (syntax-e a) (syntax-e b)))
[(debug FILENAME)
(cond
[(not (string? (syntax-e #'FILENAME)))
(raise-syntax-error #f "Debugging filename must be a string" stx #'FILENAME)]
[debug (raise-syntax-error #f "Multiple debug declarations" stx)]
[else (set! debug (syntax-e #'FILENAME))])]
[(suppress) (set! suppress #t)]
[(src-pos) (set! src-pos #t)]
[(error EXPRESSION)
(if error
(raise-syntax-error #f "Multiple error declarations" stx)
(set! error #'EXPRESSION))]
[(tokens DEF ...)
(begin
(when tokens
(raise-syntax-error #f "Multiple tokens declarations" stx))
(let ((defs (syntax->list #'(DEF ...))))
(for ([d (in-list defs)]
#:unless (identifier? d))
(raise-syntax-error #f "Token-group name must be an identifier" stx d))
(set! tokens defs)))]
[(start symbol ...)
(let ([symbols (syntax->list #'(symbol ...))])
(for ([sym (in-list symbols)]
#:unless (identifier? sym))
(raise-syntax-error #f "Start symbol must be a symbol" stx sym))
(when start
(raise-syntax-error #f "Multiple start declarations" stx))
(when (null? symbols)
(raise-syntax-error #f "Missing start symbol" stx arg))
(set! start symbols))]
[(end SYMBOLS ...)
(let ((symbols (syntax->list #'(SYMBOLS ...))))
(for ([sym (in-list symbols)]
#:unless (identifier? sym))
(raise-syntax-error #f "End token must be a symbol" stx sym))
(let ([d (duplicate-list? (map syntax-e symbols))])
(when d
(raise-syntax-error #f (format "Duplicate end token definition for ~a" d) stx arg))
(when (null? symbols)
(raise-syntax-error #f "end declaration must contain at least 1 token" stx arg))
(when end
(raise-syntax-error #f "Multiple end declarations" stx))
(set! end symbols)))]
[(precs DECLS ...)
(if precs
(raise-syntax-error #f "Multiple precs declarations" stx)
(set! precs (syntax/loc arg (DECLS ...))))]
[(grammar PRODS ...)
(if grammar
(raise-syntax-error #f "Multiple grammar declarations" stx)
(set! grammar (syntax/loc arg (PRODS ...))))]
[(yacc-output FILENAME)
(cond
[(not (string? (syntax-e #'FILENAME)))
(raise-syntax-error #f "Yacc-output filename must be a string" stx #'FILENAME)]
[yacc-output
(raise-syntax-error #f "Multiple yacc-output declarations" stx)]
[else
(set! yacc-output (syntax-e #'FILENAME))])]
[_ (raise-syntax-error #f "argument must match (debug filename), (error expression), (tokens def ...), (start non-term), (end tokens ...), (precs decls ...), or (grammar prods ...)" stx arg)]))
(unless tokens
(raise-syntax-error #f "missing tokens declaration" stx))
(unless error
@ -160,7 +113,7 @@
(raise-syntax-error #f "missing end declaration" stx))
(unless start
(raise-syntax-error #f "missing start declaration" stx))
(let-values (((table all-term-syms actions check-syntax-fix)
(let-values ([(table all-term-syms actions check-syntax-fix)
(build-parser (if debug debug "")
src-pos
suppress
@ -168,66 +121,51 @@
start
end
precs
grammar)))
grammar)])
(when (and yacc-output (not (string=? yacc-output "")))
(with-handlers [(exn:fail:filesystem?
(lambda (e)
(eprintf
"Cannot write yacc-output to file \"~a\"\n"
yacc-output)))]
(λ (e) (eprintf "Cannot write yacc-output to file \"~a\"\n" yacc-output)))]
(call-with-output-file yacc-output
(lambda (port)
(λ (port)
(display-yacc (syntax->datum grammar)
tokens
(map syntax->datum start)
(if precs
(syntax->datum precs)
#f)
(and precs (syntax->datum precs))
port))
#:exists 'truncate)))
(with-syntax ((check-syntax-fix check-syntax-fix)
(err error)
(ends end)
(starts start)
(debug debug)
(table (convert-parse-table table))
(all-term-syms all-term-syms)
(actions actions)
(src-pos src-pos))
(syntax
(begin
check-syntax-fix
(parser-body debug err (quote starts) (quote ends) table all-term-syms actions src-pos)))))))
(_
(raise-syntax-error #f
"parser must have the form (parser args ...)"
stx))))
(with-syntax ([check-syntax-fix check-syntax-fix]
[err error]
[ends end]
[starts start]
[debug debug]
[table (convert-parse-table table)]
[all-term-syms all-term-syms]
[actions actions]
[src-pos src-pos])
#'(begin
check-syntax-fix
(parser-body debug err (quote starts) (quote ends) table all-term-syms actions src-pos)))))]
[_ (raise-syntax-error #f "parser must have the form (parser args ...)" stx)]))
(define (reduce-stack stack num ret-vals src-pos)
(cond
((> num 0)
(let* ((top-frame (car stack))
(ret-vals
(if src-pos
(cons (stack-frame-value top-frame)
(cons (stack-frame-start-pos top-frame)
(cons (stack-frame-end-pos top-frame)
ret-vals)))
(cons (stack-frame-value top-frame) ret-vals))))
(reduce-stack (cdr stack) (sub1 num) ret-vals src-pos)))
(else (values stack ret-vals))))
[(positive? num)
(define top-frame (car stack))
(let ([ret-vals (if src-pos
(cons (stack-frame-value top-frame)
(cons (stack-frame-start-pos top-frame)
(cons (stack-frame-end-pos top-frame)
ret-vals)))
(cons (stack-frame-value top-frame) ret-vals))])
(reduce-stack (cdr stack) (sub1 num) ret-vals src-pos))]
[else (values stack ret-vals)]))
;; extract-helper : (symbol or make-token) any any -> symbol any any any
(define (extract-helper tok v1 v2)
(cond
((symbol? tok)
(values tok #f v1 v2))
((token? tok)
(values (real-token-name tok) (real-token-value tok) v1 v2))
(else (raise-argument-error 'parser
"(or/c symbol? token?)"
0
tok))))
[(symbol? tok) (values tok #f v1 v2)]
[(token? tok) (values (real-token-name tok) (real-token-value tok) v1 v2)]
[else (raise-argument-error 'parser "(or/c symbol? token?)" 0 tok)]))
;; well-formed-position-token?: any -> boolean
;; Returns true if pt is a position token whose position-token-token
@ -236,8 +174,7 @@
;; a tokenizer produces an erroneous position-token wrapped twice.
;; (as often happens when omitting return-without-pos).
(define (well-formed-token-field? t)
(or (symbol? t)
(token? t)))
(or (symbol? t) (token? t)))
(define (well-formed-position-token? pt)
(and (position-token? pt)
@ -250,24 +187,18 @@
;; extract-src-pos : position-token -> symbol any any any
(define (extract-src-pos ip)
(unless (well-formed-position-token? ip)
(raise-argument-error 'parser
"well-formed-position-token?"
0
ip))
(raise-argument-error 'parser "well-formed-position-token?" 0 ip))
(extract-helper (position-token-token ip)
(position-token-start-pos ip)
(position-token-end-pos ip)))
(define (extract-srcloc ip)
(unless (well-formed-srcloc-token? ip)
(raise-argument-error 'parser
"well-formed-srcloc-token?"
0
ip))
(let ([loc (srcloc-token-srcloc ip)])
(extract-helper (srcloc-token-token ip)
(position-token (srcloc-position loc) (srcloc-line loc) (srcloc-column loc))
(position-token (+ (srcloc-position loc) (srcloc-span loc)) #f #f))))
(raise-argument-error 'parser "well-formed-srcloc-token?" 0 ip))
(define loc (srcloc-token-srcloc ip))
(extract-helper (srcloc-token-token ip)
(position-token (srcloc-position loc) (srcloc-line loc) (srcloc-column loc))
(position-token (+ (srcloc-position loc) (srcloc-span loc)) #f #f)))
;; extract-no-src-pos : (symbol or make-token) -> symbol any any any
@ -295,24 +226,24 @@
(if (memq tok ends)
(raise-read-error "parser: Cannot continue after error"
#f #f #f #f #f)
(let ((a (find-action stack tok val start-pos end-pos)))
(let ([a (find-action stack tok val start-pos end-pos)])
(cond
((runtime-shift? a)
[(runtime-shift? a)
;; (printf "shift:~a\n" (runtime-shift-state a))
(cons (make-stack-frame (runtime-shift-state a)
val
start-pos
end-pos)
stack))
(else
stack)]
[else
;; (printf "discard input:~a\n" tok)
(let-values (((tok val start-pos end-pos)
(extract (get-token))))
(remove-input tok val start-pos end-pos))))))))
(let-values ([(tok val start-pos end-pos)
(extract (get-token))])
(remove-input tok val start-pos end-pos))])))))
(let remove-states ()
(let ((a (find-action stack 'error #f start-pos end-pos)))
(let ([a (find-action stack 'error #f start-pos end-pos)])
(cond
((runtime-shift? a)
[(runtime-shift? a)
;; (printf "shift:~a\n" (runtime-shift-state a))
(set! stack
(cons
@ -321,92 +252,83 @@
start-pos
end-pos)
stack))
(remove-input tok val start-pos end-pos))
(else
(remove-input tok val start-pos end-pos)]
[else
;; (printf "discard state:~a\n" (car stack))
(cond
((< (length stack) 2)
[(< (length stack) 2)
(raise-read-error "parser: Cannot continue after error"
#f #f #f #f #f))
(else
#f #f #f #f #f)]
[else
(set! stack (cdr stack))
(remove-states)))))))))
(remove-states)])])))))
(define (find-action stack tok val start-pos end-pos)
(unless (hash-ref all-term-syms
tok
#f)
(unless (hash-ref all-term-syms tok #f)
(if src-pos
(err #f tok val start-pos end-pos)
(err #f tok val))
(raise-read-error (format "parser: got token of unknown type ~a" tok)
#f #f #f #f #f))
(hash-ref (vector-ref table (stack-frame-state (car stack)))
tok
#f))
(hash-ref (vector-ref table (stack-frame-state (car stack))) tok #f))
(define (make-parser start-number)
(lambda (get-token)
(unless (and (procedure? get-token)
(procedure-arity-includes? get-token 0))
(error 'get-token "expected a nullary procedure, got ~e" get-token))
(let parsing-loop ((stack (make-empty-stack start-number))
(ip (get-token)))
(let-values (((tok val start-pos end-pos)
(extract ip)))
(let ((action (find-action stack tok val start-pos end-pos)))
(cond
((runtime-shift? action)
;; (printf "shift:~a\n" (runtime-shift-state action))
(parsing-loop (cons (make-stack-frame (runtime-shift-state action)
val
start-pos
end-pos)
stack)
(get-token)))
((runtime-reduce? action)
;; (printf "reduce:~a\n" (runtime-reduce-prod-num action))
(let-values (((new-stack args)
(reduce-stack stack
(runtime-reduce-rhs-length action)
null
src-pos)))
(let ((goto
(runtime-goto-state
(hash-ref
(vector-ref table (stack-frame-state (car new-stack)))
(runtime-reduce-lhs action)))))
(parsing-loop
(cons
(if src-pos
(make-stack-frame
goto
(apply (vector-ref actions (runtime-reduce-prod-num action)) args)
(if (null? args) start-pos (cadr args))
(if (null? args)
end-pos
(list-ref args (- (* (runtime-reduce-rhs-length action) 3) 1))))
(make-stack-frame
goto
(apply (vector-ref actions (runtime-reduce-prod-num action)) args)
#f
#f))
new-stack)
ip))))
((runtime-accept? action)
;; (printf "accept\n")
(stack-frame-value (car stack)))
(else
(if src-pos
(err #t tok val start-pos end-pos)
(err #t tok val))
(parsing-loop (fix-error stack tok val start-pos end-pos get-token)
(get-token))))))))))
(define ((make-parser start-number) get-token)
(unless (and (procedure? get-token)
(procedure-arity-includes? get-token 0))
(error 'get-token "expected a nullary procedure, got ~e" get-token))
(let parsing-loop ([stack (make-empty-stack start-number)]
[ip (get-token)])
(let-values ([(tok val start-pos end-pos) (extract ip)])
(let ([action (find-action stack tok val start-pos end-pos)])
(cond
[(runtime-shift? action)
;; (printf "shift:~a\n" (runtime-shift-state action))
(parsing-loop (cons (make-stack-frame (runtime-shift-state action)
val
start-pos
end-pos)
stack)
(get-token))]
[(runtime-reduce? action)
;; (printf "reduce:~a\n" (runtime-reduce-prod-num action))
(let-values ([(new-stack args)
(reduce-stack stack
(runtime-reduce-rhs-length action)
null
src-pos)])
(let ([goto
(runtime-goto-state
(hash-ref
(vector-ref table (stack-frame-state (car new-stack)))
(runtime-reduce-lhs action)))])
(parsing-loop
(cons
(if src-pos
(make-stack-frame
goto
(apply (vector-ref actions (runtime-reduce-prod-num action)) args)
(if (null? args) start-pos (cadr args))
(if (null? args)
end-pos
(list-ref args (- (* (runtime-reduce-rhs-length action) 3) 1))))
(make-stack-frame
goto
(apply (vector-ref actions (runtime-reduce-prod-num action)) args)
#f
#f))
new-stack)
ip)))]
[(runtime-accept? action)
;; (printf "accept\n")
(stack-frame-value (car stack))]
[else
(if src-pos
(err #t tok val start-pos end-pos)
(err #t tok val))
(parsing-loop (fix-error stack tok val start-pos end-pos get-token)
(get-token))]))))))
(cond
((null? (cdr starts)) (make-parser 0))
(else
(let loop ((l starts)
(i 0))
(cond
((null? l) null)
(else (cons (make-parser i) (loop (cdr l) (add1 i))))))))))
[(null? (cdr starts)) (make-parser 0)]
[else
(for/list ([(l i) (in-indexed starts)])
(make-parser i))])))

@ -7,5 +7,3 @@
(define build-deps '("rackunit-lib"))
(define pkg-desc "implementation (no documentation) part of \"br-parser-tools\"")
(define pkg-authors '(mflatt))

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