From d768d518bb885f67b11f9bfff401319240a1901f Mon Sep 17 00:00:00 2001 From: Matthew Butterick Date: Fri, 22 Apr 2016 14:05:07 -0700 Subject: [PATCH] capitalize nonliterals --- beautiful-racket-lib/br/define.rkt | 83 ++++++++++++--------- beautiful-racket/br/demo/basic/expander.rkt | 20 ++--- 2 files changed, 57 insertions(+), 46 deletions(-) diff --git a/beautiful-racket-lib/br/define.rkt b/beautiful-racket-lib/br/define.rkt index e72b121..8660397 100644 --- a/beautiful-racket-lib/br/define.rkt +++ b/beautiful-racket-lib/br/define.rkt @@ -1,9 +1,19 @@ #lang racket/base -(require (for-syntax racket/base syntax/parse racket/syntax syntax/datum syntax/strip-context) sugar/define) +(require (for-syntax racket/list racket/base syntax/parse racket/syntax syntax/datum syntax/strip-context) sugar/define) (provide (all-defined-out)) ;; everything is prefixed br: whether it needs it or not so it can be stripped by #lang br +(define-for-syntax (generate-literals pats) + ;; generate literals for any symbols that are not ... or _ or UPPERCASE + (for*/list ([pat-arg (in-list (flatten (map (λ(stx) (or (syntax->list stx) stx)) (syntax->list pats))))] + [pat-datum (in-value (syntax->datum pat-arg))] + #:when (and (symbol? pat-datum) + (not (eq? pat-datum '...)) (not (eq? pat-datum '_)) + (not (let ([str (symbol->string pat-datum)]) + (equal? (string-upcase str) str))))) + pat-arg)) + ;; todo: support `else` case (define-syntax (br:define-cases stx) (define-syntax-class syntaxed-id @@ -29,14 +39,15 @@ ;; syntax matcher [(_ top-id:syntaxed-id [(syntax pat) body ...] ...+) - #'(define-syntax top-id.name (λ (stx) - (define result - (syntax-case stx () - [pat body ...] ... - [else (raise-syntax-error 'define-cases (format "no matching case for syntax pattern `~a`" (syntax->datum stx)) (syntax->datum #'top-id.name))])) - (if (not (syntax? result)) - (datum->syntax stx result) - result)))] + (with-syntax ([(LITERAL ...) (generate-literals #'(pat ...))]) + #'(define-syntax top-id.name (λ (stx) + (define result + (syntax-case stx (LITERAL ...) + [pat body ...] ... + [else (raise-syntax-error 'define-cases (format "no matching case for syntax pattern `~a`" (syntax->datum stx)) (syntax->datum #'top-id.name))])) + (if (not (syntax? result)) + (datum->syntax stx result) + result))))] ;; function matcher [(_ top-id:id [(_ pat-arg ... . rest-arg) body ...] ...) @@ -51,7 +62,7 @@ (define (foo-func) 'got-foo-func) (br:define-cases #'op [#'(_ "+") #''got-plus] - [#'(_ arg) #''got-something-else] + [#'(_ ARG) #''got-something-else] [#'(_) #'(foo-func)] [#'_ #'foo-val]) @@ -93,16 +104,16 @@ ;; syntax [(_ (syntax (id pat-arg ... . rest-arg)) body ...) ; (define #'(foo arg) #'(+ arg arg)) - #'(br:define-cases (syntax id) [(syntax (_ pat-arg ... . rest-arg)) body ...])] + #'(br:define-cases (syntax id) [(syntax (_ pat-arg ... . rest-arg)) body ...])] [(_ sid:syntaxed-id sid2:syntaxed-id) ; (define #'f1 #'f2) - #'(define-syntax sid.name (make-rename-transformer sid2))] + #'(define-syntax sid.name (make-rename-transformer sid2))] [(_ (syntax id) (syntax thing)) ; (define #'f1 #'42) - #'(br:define-cases (syntax id) [#'_ (syntax thing)])] + #'(br:define-cases (syntax id) [#'_ (syntax thing)])] [(_ (sid:syntaxed-id stx-arg ...) expr ...) ; (define (#'f1 stx) expr ...) - (raise-syntax-error 'define "definition of a syntax transformer must use lambda notation, because otherwise it's too easy to confuse the compile-time shape and the run-time shape" (syntax->datum #'sid.name))] + (raise-syntax-error 'define "definition of a syntax transformer must use lambda notation, because otherwise it's too easy to confuse the compile-time shape and the run-time shape" (syntax->datum #'sid.name))] [(_ sid:syntaxed-id (λ (stx-arg ...) expr ...)) ; (define #'f1 (λ(stx) expr ...) #:fail-when (not (= (length (syntax->datum #'(stx-arg ...))) 1)) @@ -118,16 +129,16 @@ (br:define #'plusser #'plus) (check-equal? (plusser 42) +) (check-equal? plusser +) - (br:define #'(times arg) #'(* arg arg)) + (br:define #'(times ARG) #'(* ARG ARG)) (check-equal? (times 10) 100) (br:define #'timeser #'times) (check-equal? (timeser 12) 144) (br:define #'fortytwo #'42) (check-equal? fortytwo 42) (check-equal? (let () - (br:define #'(foo x) + (br:define #'(foo X) (with-syntax ([zam +]) - #'(zam x x))) (foo 42)) 84) + #'(zam X X))) (foo 42)) 84) ;; todo: error from define not trapped by check-exn #;(check-exn exn:fail:syntax? (λ _ (br:define (#'times stx stx2) #'*))) (begin @@ -137,28 +148,28 @@ (define-syntax-rule (br:debug-define (syntax (id pat-arg ... . rest-arg)) body-exp) - (br:define #'(id pat-arg ... . rest-arg) - #`(begin - (for-each displayln - (list - (format "input pattern = #'~a" '#,'(id pat-arg ... . rest-arg)) - (format "output pattern = #'~a" (cadr '#,'body-exp)) - (format "invoked as = ~a" (syntax->datum #'(id pat-arg ... . rest-arg))) - (format "expanded as = ~a" '#,(syntax->datum body-exp)) - (format "evaluated as = ~a" #,body-exp))) - #,body-exp))) + (br:define #'(id pat-arg ... . rest-arg) + #`(begin + (for-each displayln + (list + (format "input pattern = #'~a" '#,'(id pat-arg ... . rest-arg)) + (format "output pattern = #'~a" (cadr '#,'body-exp)) + (format "invoked as = ~a" (syntax->datum #'(id pat-arg ... . rest-arg))) + (format "expanded as = ~a" '#,(syntax->datum body-exp)) + (format "evaluated as = ~a" #,body-exp))) + #,body-exp))) (module+ test - (require rackunit racket/port) - (parameterize ([current-output-port (open-output-nowhere)]) - (check-equal? (let () - (br:debug-define #'(foo X Y Z) - #'(apply + (list X Y Z))) - (foo 1 2 3)) 6) - (check-equal? (let () - (br:debug-define #'(foo X ...) #'(apply * (list X ...))) - (foo 10 11 12)) 1320))) + (require rackunit racket/port) + (parameterize ([current-output-port (open-output-nowhere)]) + (check-equal? (let () + (br:debug-define #'(foo X Y Z) + #'(apply + (list X Y Z))) + (foo 1 2 3)) 6) + (check-equal? (let () + (br:debug-define #'(foo X ...) #'(apply * (list X ...))) + (foo 10 11 12)) 1320))) diff --git a/beautiful-racket/br/demo/basic/expander.rkt b/beautiful-racket/br/demo/basic/expander.rkt index 2830953..23283d2 100644 --- a/beautiful-racket/br/demo/basic/expander.rkt +++ b/beautiful-racket/br/demo/basic/expander.rkt @@ -104,26 +104,26 @@ (define (basic:or . args) (cond->int (ormap true? args))) (define-cases #'expr - [#'(_ COMP-EXPR "AND" EXPR) #'(basic:and COMP-EXPR EXPR)] - [#'(_ COMP-EXPR "OR" EXPR) #'(basic:or COMP-EXPR EXPR)] + [#'(_ COMP-EXPR "AND" SUBEXPR) #'(basic:and COMP-EXPR SUBEXPR)] + [#'(_ COMP-EXPR "OR" SUBEXPR) #'(basic:or COMP-EXPR SUBEXPR)] [#'(_ COMP-EXPR) #'COMP-EXPR]) (define-cases #'comp-expr [#'(_ LEXPR "=" REXPR) #'(comp-expr LEXPR "equal?" REXPR)] ; special case because = is overloaded [#'(_ LEXPR op REXPR) (inject-syntax ([#'OP (string->symbol (syntax->datum #'op))]) #'(cond->int (OP LEXPR REXPR)))] - [#'(_ expr) #'expr]) + [#'(_ ARG) #'ARG]) (define <> (compose1 not equal?)) (define-cases #'sum - [#'(_ term "+" sum) #'(+ term sum)] - [#'(_ term "-" sum) #'(- term sum)] - [#'(_ term) #'term]) + [#'(_ TERM "+" SUM) #'(+ TERM SUM)] + [#'(_ TERM "-" SUM) #'(- TERM SUM)] + [#'(_ TERM) #'TERM]) (define-cases #'product - [#'(_ factor "*" product) #'(* factor product)] - [#'(_ factor "/" product) #'(/ factor product)] - [#'(_ factor) #'factor]) + [#'(_ FACTOR "*" PRODUCT) #'(* FACTOR PRODUCT)] + [#'(_ FACTOR "/" PRODUCT) #'(/ FACTOR PRODUCT)] + [#'(_ FACTOR) #'FACTOR]) (define print-list list) @@ -136,7 +136,7 @@ [(list print-list-item ...) (for-each displayln print-list-item)])) (define (TAB num) (make-string num #\space)) -(define #'(INT EXPR ...) #'(inexact->exact (truncate (expr EXPR ...)))) +(define #'(INT ARG ...) #'(inexact->exact (truncate (expr ARG ...)))) (define (SIN num) (sin num)) (define (ABS num) (inexact->exact (abs num))) (define (RND num) (* (random) num))