blob: 50a5f9d3d8c00cae62e7552f86a078a3565714cf (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
#lang scheme/base
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; PARSEQ.PLT
;; A Parser Combinator library.
;;
;; Bonzai Lab, LLC. All rights reserved.
;;
;; Licensed under LGPL.
;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; reader.ss - move make-reader & Reader/c here
;; yc 1/18/2010 - first version
;; yc 1/21/2010 - make-reader to take on additional default params
(require "depend.ss"
"input.ss"
"primitive.ss"
"combinator.ss"
(prefix-in c: scheme/contract)
)
;; use this to create a reader that will read the bytes if the parse succeeds.
(define (make-reader parser #:sof? (sof? #t) #:eof? (eof? #t) #:default (default #f))
(lambda (in #:sof? (sof? sof?) #:eof? (eof? eof?) #:default (default default))
(let-values (((v in)
((seq (if sof? SOF (return #t))
v <- parser
(if eof? EOF (return #t))
(return v)) (make-input in))))
(unless (failed? v) (read-bytes* in))
(if (failed? v)
default
v))))
(define Reader/c (c:->* (Input/c)
(#:sof? boolean? #:eof? boolean? #:default c:any/c)
c:any))
(provide Reader/c)
(c:provide/contract
(make-reader (c:->* (Parser/c)
(#:sof? boolean? #:eof? boolean? #:default c:any/c)
Reader/c))
)
|
