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
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
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, 59 Temple Place, Suite 330, Boston, MA 02111, USA.
;;
;; As a special exception, the Free Software Foundation gives permission
;; for additional uses of the text contained in its release of SCM.
;;
;; The exception is that, if you link the SCM 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 SCM 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 SCM. If you copy
;; code from other Free Software Foundation releases into a copy of
;; SCM, 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 SCM, 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))
|