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Diffstat (limited to 'Iedline.scm')
| -rw-r--r-- | Iedline.scm | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/Iedline.scm b/Iedline.scm new file mode 100644 index 0000000..cbeb265 --- /dev/null +++ b/Iedline.scm @@ -0,0 +1,103 @@ +;; Copyright (C) 1994, 1995 Free Software Foundation, Inc. +;; +;; This program is free software; you can redistribute it and/or modify +;; it under the terms of the GNU General Public License as published by +;; the Free Software Foundation; either version 2, or (at your option) +;; any later version. +;; +;; This program is distributed in the hope that it will be useful, +;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;; GNU General Public License for more details. +;; +;; You should have received a copy of the GNU General Public License +;; along with this software; see the file COPYING. If not, write to +;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. +;; +;; As a special exception, the Free Software Foundation gives permission +;; for additional uses of the text contained in its release of GUILE. +;; +;; The exception is that, if you link the GUILE library with other files +;; to produce an executable, this does not by itself cause the +;; resulting executable to be covered by the GNU General Public License. +;; Your use of that executable is in no way restricted on account of +;; linking the GUILE library code into it. +;; +;; This exception does not however invalidate any other reasons why +;; the executable file might be covered by the GNU General Public License. +;; +;; This exception applies only to the code released by the +;; Free Software Foundation under the name GUILE. If you copy +;; code from other Free Software Foundation releases into a copy of +;; GUILE, as the General Public License permits, the exception does +;; not apply to the code that you add in this way. To avoid misleading +;; anyone as to the status of such modified files, you must delete +;; this exception notice from them. +;; +;; If you write modifications of your own for GUILE, it is your choice +;; whether to permit this exception to apply to your modifications. +;; If you do not wish that, delete this exception notice. + +;; "Iedline.scm" Scheme interface to readline library +;; Author: Radey Shouman + +;; Change both current-input-port and current-output-port to +;; allow line editing of input. +;; All output goes through a soft port in order to detect prompt +;; lines, i.e. lines unterminated by a newline. + +(define (make-edited-line-port) + (let ((prompt "") + (outp (default-output-port)) + (inp (default-input-port)) + (strp (call-with-input-string "" identity))) + (make-soft-port + (vector (lambda (c) + (write-char c outp)) + (lambda (s) + (display s outp) + (or (zero? (string-length s)) + (eq? #\newline (string-ref s (- (string-length s) 1))) + (begin + (set! prompt (string-append "\r" s)) + (force-output outp)))) + (lambda () + (force-output outp)) + (lambda () + (let tail ((c (read-char strp))) + (if (char? c) c + (let ((str (read-edited-line prompt))) + (if (string? str) + (let ((n (string-length str))) + (add-history str) + (vector-set-length! str (+ 1 n)) + (string-set! str n #\newline) + (set! strp (call-with-input-string + str identity)) + (tail (read-char strp))) + str))))) + #f) + OPEN_BOTH))) + +(define line-editing + (let ((edit-port #f) + (oiport #f) + (ooport #f)) + (lambda arg + (define past edit-port) + (cond ((null? arg)) + ((and (car arg) (not edit-port)) + (set! edit-port (make-edited-line-port)) + (set! oiport (set-current-input-port edit-port)) + (set! ooport (set-current-output-port edit-port))) + (edit-port + (set-current-input-port oiport) + (set-current-output-port ooport) + (set! edit-port #f))) + past))) + +(and + (if (provided? 'unix) (isatty? (current-input-port)) #t) + (eq? (current-input-port) (default-input-port)) + (not (getenv "EMACS")) + (line-editing #t)) |