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;;; "obj2str.scm", write objects to a string.
;Copyright (C) 1993, 1994 Aubrey Jaffer
;
;Permission to copy this software, to redistribute it, and to use it
;for any purpose is granted, subject to the following restrictions and
;understandings.
;
;1. Any copy made of this software must include this copyright notice
;in full.
;
;2. I have made no warrantee or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3. In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.
(require 'string-port)
(define (object->string obj)
(cond ((symbol? obj) (symbol->string obj))
((number? obj) (number->string obj))
(else
(call-with-output-string
(lambda (port) (write obj port))))))
; File: "obj2str.scm" (c) 1991, Marc Feeley
;(require 'generic-write)
; (object->string obj) returns the textual representation of 'obj' as a
; string.
;
; Note: (write obj) = (display (object->string obj))
;(define (object->string obj)
; (let ((result '()))
; (generic-write obj #f #f (lambda (str) (set! result (cons str result)) #t))
; (reverse-string-append result)))
; (object->limited-string obj limit) returns a string containing the first
; 'limit' characters of the textual representation of 'obj'.
(define (object->limited-string obj limit)
(require 'generic-write)
(let ((result '()) (left limit))
(generic-write obj #f #f
(lambda (str)
(let ((len (string-length str)))
(if (> len left)
(begin
(set! result (cons (substring str 0 left) result))
(set! left 0)
#f)
(begin
(set! result (cons str result))
(set! left (- left len))
#t)))))
(reverse-string-append result)))
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