racket/collects/web-server/lang/util.ss
Jay McCarthy 69d9e3fd4f Adding redundant req
svn: r16009
2009-09-14 21:08:33 +00:00

92 lines
3.1 KiB
Scheme

#lang scheme/base
(require (for-template scheme/base)
scheme/list
scheme/contract)
(provide/contract
[transformer? (parameter/c boolean?)]
[recertify (syntax? syntax? . -> . syntax?)]
[current-code-labeling (parameter/c (syntax? . -> . syntax?))]
[generate-formal ((symbol?) ((or/c false/c syntax?)) . ->* . (values syntax? syntax?))]
[formals-list (syntax? . -> . (listof syntax?))]
[make-define-case ((syntax? . -> . syntax?) . -> . (syntax? . -> . syntax?))]
[make-module-case ((syntax? . -> . syntax?) . -> . (syntax? . -> . syntax?))]
[make-lang-module-begin ((bytes? . -> . (-> symbol?)) (syntax? . -> . syntax?) . -> . (syntax? . -> . syntax?))]
[bound-identifier-member? (syntax? (listof syntax?) . -> . boolean?)])
(define transformer? (make-parameter #f))
(define (recertify old-expr expr)
(syntax-recertify expr old-expr (current-code-inspector) #f))
(define current-code-labeling
(make-parameter
(lambda (stx)
(datum->syntax stx 'error))))
(define (generate-formal sym-name [stx-base #f])
(let ([name (datum->syntax stx-base (gensym sym-name))])
(with-syntax ([(#%plain-lambda (formal) ref-to-formal)
(if (syntax-transforming?)
(local-expand #`(#%plain-lambda (#,name) #,name) 'expression empty)
#`(#%plain-lambda (#,name) #,name))])
(values #'formal #'ref-to-formal))))
(define (formals-list stx)
(syntax-case stx ()
[v (identifier? #'v)
(list #'v)]
[(v ...)
(syntax->list #'(v ...))]
[(v ... . rv)
(list* #'rv (syntax->list #'(v ...)))]))
(define ((make-define-case inner) stx)
(recertify
stx
(syntax-case stx (define-values define-syntaxes define-values-for-syntax)
[(define-values (v ...) ve)
(let-values ([(nve) (inner #'ve)])
(quasisyntax/loc stx
(define-values (v ...) #,nve)))]
[(define-syntaxes (v ...) ve)
stx]
[(define-values-for-syntax (v ...) ve)
stx]
[(#%require spec ...)
stx]
[expr
(inner #'expr)])))
(define ((make-module-case inner) stx)
(recertify
stx
(syntax-case* stx (#%provide) free-identifier=?
[(#%provide spec ...)
stx]
[_
(inner stx)])))
(define ((make-lang-module-begin make-labeling transform) stx)
(recertify
stx
(syntax-case stx ()
[(mb forms ...)
(with-syntax ([(pmb body ...)
(local-expand (quasisyntax/loc stx
(#%module-begin (require web-server/lang/lang-api) forms ...))
'module-begin
empty)])
(define base-labeling (make-labeling (string->bytes/utf-8 (format "~a" (syntax->datum stx)))))
(define new-defs
(parameterize ([current-code-labeling
(lambda (stx) (datum->syntax stx (base-labeling)))])
(map transform (syntax->list #'(body ...)))))
(quasisyntax/loc stx
(pmb #,@new-defs)))])))
(define (bound-identifier-member? id ids)
(ormap
(lambda (an-id)
(bound-identifier=? id an-id))
ids))