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beautiful-racket/beautiful-racket-lib/br/syntax.rkt

158 lines
5.5 KiB
Racket

#lang racket/base
(require (for-syntax
racket/base
racket/syntax
br/private/generate-literals)
racket/list
racket/match
racket/syntax
racket/format
syntax/stx
syntax/strip-context
br/define
br/private/syntax-flatten)
(provide (all-defined-out)
syntax-flatten
stx-map
(rename-out [strip-context strip-bindings]
[replace-context replace-bindings]
[stx-map syntax-map]
[syntax-flatten stx-flatten]
[prefix-id prefix-ids]
[suffix-id suffix-ids]
[infix-id infix-ids]))
(module+ test
(require rackunit))
(define-macro (syntax-match STX-ARG [(syntax PATTERN) BODY ...] ...)
#'(syntax-case STX-ARG ()
[PATTERN BODY ...] ...))
(define-macro-cases with-pattern
[(_ () . BODY) #'(begin . BODY)]
[(_ ([PAT0 STX0] PAT+STX ...) . BODY)
(with-syntax ([(LITERAL ...) (generate-literals #'PAT0)])
#'(syntax-case STX0 (LITERAL ...)
[PAT0 (with-pattern (PAT+STX ...) (let () . BODY))]
[else (raise-syntax-error 'with-pattern
(format "unable to match pattern ~a" 'PAT0) STX0)]))])
(define (check-syntax-list-argument caller-name arg)
(cond
[(and (syntax? arg) (syntax->list arg))]
[(list? arg) arg]
[else (raise-argument-error caller-name "list of syntax, or syntaxed list" arg)]))
(define-macro (define-listy-macro MACRO-ID LIST-FUNC)
#'(define-macro (MACRO-ID STX-LIST LITERALS . MATCHERS)
#'(LIST-FUNC
(λ(stx-item)
(with-handlers ([exn:fail:syntax? (λ (exn) #f)])
(syntax-case stx-item LITERALS
. MATCHERS)))
(check-syntax-list-argument 'MACRO-ID STX-LIST))))
(define-listy-macro syntax-case-partition partition)
(define-listy-macro syntax-case-filter filter)
(define-listy-macro syntax-case-map map)
(define-macro (reformat-id FMT ID0 ID ...)
#'(format-id ID0 FMT ID0 ID ...))
(define-macro (format-string FMT ID0 ID ...)
#'(datum->syntax ID0 (format FMT (syntax->datum ID0) (syntax->datum ID) ...)))
#|
(define (format-string FMT ID0 . IDS)
(datum->syntax ID0 (apply format FMT (syntax->datum ID0) (map syntax->datum IDS))))
|#
(define (->unsyntax x)
(if (syntax? x) (syntax->datum x) x))
(define (fix-base loc-arg prefixes base-or-bases suffixes)
(define single-mode? (and (not (list? base-or-bases)) (not (syntax->list base-or-bases))))
(define bases (if single-mode? (list base-or-bases) (or (syntax->list base-or-bases) base-or-bases)))
(define (stx-join stxs) (apply string-append (map (compose1 ~a ->unsyntax) stxs)))
(define result (map (λ (base) (format-id base "~a~a~a" (stx-join prefixes) (syntax-e base) (stx-join suffixes)
#:source loc-arg)) bases))
(if single-mode? (car result) result))
(define (prefix-id #:source [loc-arg #f] . args)
((match-lambda
[(list prefixes ... base-or-bases)
(fix-base loc-arg prefixes base-or-bases empty)]) args))
(define (infix-id #:source [loc-arg #f] . args)
((match-lambda
[(list prefix base-or-bases suffixes ...)
(fix-base loc-arg (list prefix) base-or-bases suffixes)]) args))
(define (suffix-id #:source [loc-arg #f] . args)
((match-lambda
[(list base-or-bases suffixes ...)
(fix-base loc-arg empty base-or-bases suffixes)]) args))
(module+ test
(define-check (check-stx-equal? stx1 stx2)
(define stxs (list stx1 stx2))
(apply equal? (map syntax->datum stxs)))
(check-stx-equal? (prefix-id "foo" "bar" #'id) #'foobarid)
(check-stx-equal? (infix-id "foo" #'id "bar" "zam") #'fooidbarzam)
(check-stx-equal? (suffix-id #'id "foo" "bar" "zam") #'idfoobarzam)
(for-each check-stx-equal? (suffix-id #'(this that) "@") (list #'this@ #'that@)))
(define-macro-cases syntax-property*
[(_ STX 'PROP0) ; read one
#'(syntax-property STX 'PROP0)]
[(_ STX 'PROP0 'PROP ...) ; read multiple
#'(cons (syntax-property* STX 'PROP0)
(let ([result (syntax-property* STX 'PROP ...)])
(if (pair? result)
result
(list result))))]
[(_ STX ['PROP0 VAL0 . PRESERVED0]) ; write one
#'(syntax-property STX 'PROP0 VAL0 . PRESERVED0)]
[(_ STX ['PROP0 VAL0 . PRESERVED0] ['PROP VAL . PRESERVED] ...) ; write multiple
#'(syntax-property* (syntax-property STX 'PROP0 VAL0 . PRESERVED0) ['PROP VAL . PRESERVED] ...)])
#|
(define (syntax-property* . args)
((match-lambda*
[(list x) x]
[(list stx (list prop val others ...)) ; write one
(apply syntax-property stx prop val others)]
[(list stx (list prop val others ...) args ...) ; write multiple
#'(apply syntax-property* (apply syntax-property stx prop val others) args)]
[(list stx prop) ; read one
(syntax-property stx prop)]
[(list stx prop0 props ...) ; read multiple
(map (λ (prop) (syntax-property stx prop)) (cons prop0 props))]
[else 'huh]) args))
|#
(define (filter-stx-prop prop stxs)
(filter (λ (stx) (syntax-property stx prop)) stxs))
(module+ test
(define x (syntax-property* #'foo ['bar #t] ['zam 'boni]))
(check-false (syntax-property* x 'foo))
(check-true (syntax-property* x 'bar))
(check-equal? (syntax-property* x 'foo 'bar 'zam) '(#f #t boni)))
(define (syntax-srcloc stx)
(srcloc (syntax-source stx)
(syntax-line stx)
(syntax-column stx)
(syntax-position stx)
(syntax-span stx)))