racket/collects/syntax/private/stxparse/lib.ss
Ryan Culpepper 0feac0f636 syntax/parse:
tweaked error selection algorithm
  added tests

svn: r16533
2009-11-04 00:31:24 +00:00

127 lines
4.1 KiB
Scheme

#lang scheme/base
(require "sc.ss"
"../util.ss"
syntax/stx
syntax/kerncase
scheme/struct-info
scheme/contract/private/helpers
(for-syntax scheme/base
syntax/kerncase
"rep.ss"
(only-in "rep-data.ss" make-literalset))
(for-template scheme/base
scheme/contract/base))
(provide identifier
boolean
str
character
keyword
number
integer
exact-integer
exact-nonnegative-integer
exact-positive-integer
id
nat
char
expr
expr/c
static
atom-in-list
kernel-literals)
(define-syntax-rule (define-pred-stxclass name pred)
(define-syntax-class name #:attributes () #:opaque
(pattern x
#:fail-unless (pred (syntax-e #'x)) #f)))
(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?)
;; Aliases
(define-syntax id (make-rename-transformer #'identifier))
(define-syntax nat (make-rename-transformer #'exact-nonnegative-integer))
(define-syntax char (make-rename-transformer #'character))
(define notfound (box 'notfound))
(define-syntax-class (static pred name)
#:attributes (value)
#:description name
(pattern x:id
#:fail-unless (syntax-transforming?)
"not within the extent of a macro transformer"
#:attr value (syntax-local-value #'x (lambda () notfound))
#:fail-when (eq? (attribute value) notfound) #f
#:fail-unless (pred (attribute value)) #f))
(define-syntax-class (atom-in-list atoms name)
#:attributes ()
#:description name
(pattern x
#:fail-unless (memv (syntax-e #'x) atoms) #f))
(define-syntax-class struct-name
#:description "struct name"
#:attributes (descriptor
constructor
predicate
[accessor 1]
super
complete?)
(pattern s
#:declare s (static struct-info? "struct name")
#:with info (extract-struct-info (attribute s.value))
#:with descriptor (list-ref (attribute info) 0)
#:with constructor (list-ref (attribute info) 1)
#:with predicate (list-ref (attribute info) 2)
#:with r-accessors (reverse (list-ref (attribute info) 3))
#:with (accessor ...)
(datum->syntax #f (let ([r-accessors (attribute r-accessors)])
(if (and (pair? r-accessors) (eq? #f (car r-accessors)))
(cdr r-accessors)
r-accessors)))
#:with super (list-ref (attribute info) 5)
#:attr complete? (or (null? (attribute r-accessors))
(and (pair? (attribute r-accessors))
(not (eq? #f (car (attribute r-accessors))))))))
(define-syntax-class expr
#:attributes ()
(pattern x
#:fail-when (keyword? (syntax-e #'x)) #f))
(define-syntax-class (expr/c ctc)
#:attributes (c)
(pattern x:expr
#:with c #`(contract #,ctc
x
(quote #,(string->symbol (or (build-src-loc-string #'x) "")))
(quote #,(or '<this-macro>))
(quote-syntax #,(syntax/loc #'x (<there>))))))
;; Literal sets
(define-syntax kernel-literals
(make-literalset
(list* (quote-syntax module)
(quote-syntax #%plain-module-begin)
(quote-syntax #%require)
(quote-syntax #%provide)
(for/list ([id (kernel-form-identifier-list)])
(list (syntax-e id) id)))))