racket/collects/macro-debugger/stxclass/private/lib.ss
Matthew Flatt 24739359e4 Ryan's macro-stepper patches
svn: r9794
2008-05-10 11:02:47 +00:00

259 lines
9.0 KiB
Scheme

#lang scheme/base
(require "sc.ss"
syntax/stx
syntax/kerncase
scheme/struct-info
scheme/private/contract-helpers
(for-syntax scheme/base
"rep.ss")
(for-template scheme/base
scheme/contract))
(provide (all-defined-out))
(define-syntax-rule (define-pred-stxclass name pred)
(define-basic-syntax-class name
([datum 0])
(lambda (x)
(let ([d (if (syntax? x) (syntax-e x) x)])
(if (pred d)
(list d)
(fail-sc x #:pattern 'name))))))
(define-pred-stxclass identifier symbol?)
(define-pred-stxclass boolean boolean?)
(define-pred-stxclass str string?)
(define-pred-stxclass character char?)
(define-pred-stxclass keyword keyword?)
(define-pred-stxclass number number?)
(define-pred-stxclass integer integer?)
(define-pred-stxclass exact-integer exact-integer?)
(define-pred-stxclass exact-nonnegative-integer exact-nonnegative-integer?)
(define-pred-stxclass exact-positive-integer exact-positive-integer?)
(define-syntax-rule (define-kw-stxclass name kw)
(define-basic-syntax-class name
()
(lambda (x)
(if (and (identifier? x) (free-identifier=? x (quote-syntax kw)))
null
(fail-sc x #:pattern 'name)))))
(define-kw-stxclass lambda-kw #%lambda)
(define-kw-stxclass define-values-kw define-values)
(define-kw-stxclass define-syntaxes-kw define-syntaxes)
(define-syntax-class define-values-form
(pattern (kw:define-values-kw (var:identifier ...) rhs)))
(define-syntax-class define-syntaxes-form
(pattern (kw:define-syntaxes-kw (var:identifier ...) rhs)))
(define-syntax-class definition-form
(union define-values-form
define-syntaxes-form))
(define-basic-syntax-class static
([datum 0] [value 0])
(lambda (x)
(if (identifier? x)
(let/ec escape
(define (bad)
(escape
(fail-sc x
#:pattern 'static
#:reason "not bound as syntax")))
(let ([value (syntax-local-value x bad)])
(list (syntax-e x) value)))
(fail-sc x
#:pattern 'static
#:reason "not an identifier"))))
(define-basic-syntax-class struct-name
([descriptor 0]
[constructor 0]
[predicate 0]
[accessor 1]
[super 0]
[complete? 0])
(lambda (x)
(if (identifier? x)
(let/ec escape
(define (bad)
(escape
(fail-sc x
#:pattern 'struct-name
#:reason "not bound as a struct name")))
(let ([value (syntax-local-value x bad)])
(unless (struct-info? value) (bad))
(let ([lst (extract-struct-info value)])
(let ([descriptor (list-ref lst 0)]
[constructor (list-ref lst 1)]
[predicate (list-ref lst 2)]
[accessors (list-ref lst 3)]
[super (list-ref lst 5)])
(let ([r-accessors (reverse accessors)])
(list descriptor
constructor
predicate
(if (and (pair? r-accessors) (eq? #f (car r-accessors)))
(cdr r-accessors)
r-accessors)
super
(or (null? r-accessors) (not (eq? #f (car r-accessors))))))))))
(fail-sc x
#:pattern 'struct-name
#:reason "not bound as a struct name"))))
(define-basic-syntax-class expr/local-expand
([expanded 0])
(lambda (x)
(list (local-expand x 'expression null))))
(define-basic-syntax-class expr/head-local-expand
([expanded 0])
(lambda (x)
(list (local-expand x 'expression (kernel-form-identifier-list)))))
(define-basic-syntax-class block/head-local-expand
([expanded-block 0]
[expanded 1]
[def 1]
[vdef 1]
[sdef 1]
[expr 1])
(lambda (x)
(let-values ([(ex1 ex2 defs vdefs sdefs exprs)
(head-local-expand-syntaxes x #f #t)])
(list ex1 ex2 defs vdefs sdefs exprs))))
(define-basic-syntax-class internal-definitions
([expanded-block 0]
[expanded 1]
[def 1]
[vdef 1]
[sdef 1]
[expr 1])
(lambda (x)
(let-values ([(ex1 ex2 defs vdefs sdefs exprs)
(head-local-expand-syntaxes x #t #f)])
(list ex1 ex2 defs vdefs sdefs exprs))))
;; head-local-expand-syntaxes : syntax boolean boolean -> stxs ^ 6
;; Setting allow-def-after-expr? allows def/expr interleaving.
;; Setting need-expr? requires at least one expr to be present.
(define (head-local-expand-syntaxes x allow-def-after-expr? need-expr?)
(let ([intdef (syntax-local-make-definition-context)]
[ctx '(block)])
(let loop ([x x] [ex null] [defs null] [vdefs null] [sdefs null] [exprs null])
(cond [(stx-pair? x)
(let ([ee (local-expand (stx-car x)
ctx
(kernel-form-identifier-list)
intdef)])
(syntax-case ee (begin define-values define-syntaxes)
[(begin e ...)
(loop (append (syntax->list #'(e ...)) (stx-cdr x)) ex defs vdefs sdefs exprs)]
[(begin . _)
(raise-syntax-error #f "bad begin form" ee)]
[(define-values (var ...) rhs)
(andmap identifier? (syntax->list #'(var ...)))
(begin
(when (and (pair? exprs) (not allow-def-after-expr?))
(raise-syntax-error #f "definition after expression" ee))
(syntax-local-bind-syntaxes (syntax->list #'(var ...)) #f intdef)
(loop (stx-cdr x)
(cons ee ex)
(cons ee defs)
(cons ee vdefs)
sdefs
exprs))]
[(define-values . _)
(raise-syntax-error #f "bad define-values form" ee)]
[(define-syntaxes (var ...) rhs)
(andmap identifier? (syntax->list #'(var ...)))
(begin
(when (and (pair? exprs) (not allow-def-after-expr?))
(raise-syntax-error #f "definition after expression" ee))
(syntax-local-bind-syntaxes (syntax->list #'(var ...))
#'rhs
intdef)
(loop (stx-cdr x)
(cons ee ex)
(cons ee defs)
vdefs
(cons ee sdefs)
exprs))]
[(define-syntaxes . _)
(raise-syntax-error #f "bad define-syntaxes form" ee)]
[_
(loop (stx-cdr x)
(cons ee ex)
defs
vdefs
sdefs
(cons ee exprs))]))]
[(stx-null? x)
(let ([ex (reverse ex)])
(values ex
ex
(reverse defs)
(reverse vdefs)
(reverse sdefs)
(reverse exprs)))]))))
(define-syntax-rule (define-contract-stxclass name c)
(define-basic-syntax-class* (name)
([orig-stx 0])
(lambda (x)
(list #`(contract c
#,x
(quote #,(string->symbol (or (build-src-loc-string x) "")))
(quote #,(or (current-macro-name) '<this-macro>))
(quote-syntax #,(syntax/loc x (<there>))))
x))))
(define-contract-stxclass expr/num number?)
(define-contract-stxclass expr/num->num (-> number? number?))
(define-basic-syntax-class* (expr)
()
(lambda (x)
(if (not (keyword? (syntax-e x)))
(list x)
(fail-sc x #:pattern 'expr #:reason "keyword"))))
;; FIXME: hack
(define expr/c-use-contracts? (make-parameter #t))
(define-basic-syntax-class* (expr/c contract)
([orig-stx 0])
(lambda (x c)
(if (not (keyword? (syntax-e x)))
(if (expr/c-use-contracts?)
(list #`(contract #,c
#,x
(quote #,(string->symbol
(or (build-src-loc-string x) "")))
(quote #,(or (current-macro-name) '<this-macro>))
(quote-syntax #,(syntax/loc x (<there>))))
x)
(list x x))
(fail-sc x #:pattern 'expr #:reason "keyword"))))
(define-basic-syntax-class (term parser)
()
(lambda (x p) (p x)))
(define-basic-syntax-class (term/pred pred)
()
(lambda (x p)
(if (p x)
null
(fail-sc x #:pattern 'term/pred))))
;; Aliases
(define-syntax id (make-rename-transformer #'identifier))
(define-syntax nat (make-rename-transformer #'exact-nonnegative-integer))
(define-syntax char (make-rename-transformer #'character))