Artifact
d1c8321cc520ff9165583e8b2477844e4dfe4b9b:
;; Copyright (c) 2009 Derick Eddington. All rights reserved.
;; Licensed under an MIT-style license. My license is in the file
;; named LICENSE from the original collection this file is distributed
;; with. If this file is redistributed with some other collection, my
;; license must also be included.
#!r6rs
(library (srfi s6 basic-string-ports)
(export
(rename (open-string-input-port open-input-string))
open-output-string
get-output-string)
(import
(rnrs)
(only (scheme base) make-weak-hasheq hash-ref hash-set!))
(define accumed-ht (make-weak-hasheq))
(define (open-output-string)
(letrec ([sop
(make-custom-textual-output-port
"string-output-port"
(lambda (string start count) ; write!
(when (positive? count)
(let ([al (hash-ref accumed-ht sop)])
(hash-set! accumed-ht sop
(cons (substring string start (+ start count)) al))))
count)
#f ; get-position TODO?
#f ; set-position! TODO?
#f #| closed TODO? |# )])
(hash-set! accumed-ht sop '())
sop))
(define (get-output-string sop)
(if (output-port? sop)
(cond [(hash-ref accumed-ht sop #f)
=> (lambda (al) (apply string-append (reverse al)))]
[else
(assertion-violation 'get-output-string "not a string-output-port" sop)])
(assertion-violation 'get-output-string "not an output-port" sop)))
)