Merge from emacs-23
[bpt/emacs.git] / lisp / progmodes / xscheme.el
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1;;; xscheme.el --- run MIT Scheme under Emacs
2
ae940284 3;; Copyright (C) 1986, 1987, 1989, 1990, 2001, 2002, 2003, 2004, 2005,
114f9c96 4;; 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
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5
6;; Maintainer: FSF
7;; Keywords: languages, lisp
8
9;; This file is part of GNU Emacs.
10
b1fc2b50 11;; GNU Emacs is free software: you can redistribute it and/or modify
c5c3d778 12;; it under the terms of the GNU General Public License as published by
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13;; the Free Software Foundation, either version 3 of the License, or
14;; (at your option) any later version.
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15
16;; GNU Emacs is distributed in the hope that it will be useful,
17;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19;; GNU General Public License for more details.
20
21;; You should have received a copy of the GNU General Public License
b1fc2b50 22;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
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23
24;;; Commentary:
25
26;; A major mode for interacting with MIT Scheme.
27;;
28;; Requires MIT Scheme release 5 or later.
29;; Changes to Control-G handler require runtime version 13.85 or later.
30
31;;; Code:
32
33(require 'scheme)
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34
35;;;; Internal Variables
36
37(defvar xscheme-previous-mode)
38(defvar xscheme-previous-process-state)
39(defvar xscheme-last-input-end)
40
41(defvar xscheme-process-command-line nil
42 "Command used to start the most recent Scheme process.")
43
44(defvar xscheme-process-name "scheme"
45 "Name of xscheme process that we're currently interacting with.")
46
47(defvar xscheme-buffer-name "*scheme*"
48 "Name of xscheme buffer that we're currently interacting with.")
49
50(defvar xscheme-expressions-ring-max 30
51 "*Maximum length of Scheme expressions ring.")
52
53(defvar xscheme-expressions-ring nil
54 "List of expressions recently transmitted to the Scheme process.")
55
56(defvar xscheme-expressions-ring-yank-pointer nil
57 "The tail of the Scheme expressions ring whose car is the last thing yanked.")
58
59(defvar xscheme-running-p nil
60 "This variable, if nil, indicates that the scheme process is
61waiting for input. Otherwise, it is busy evaluating something.")
62
63(defconst xscheme-control-g-synchronization-p t
64 "If non-nil, insert markers in the scheme input stream to indicate when
65control-g interrupts were signaled. Do not allow more control-g's to be
66signaled until the scheme process acknowledges receipt.")
67
68(defvar xscheme-control-g-disabled-p nil
69 "This variable, if non-nil, indicates that a control-g is being processed
70by the scheme process, so additional control-g's are to be ignored.")
71
72(defvar xscheme-string-receiver nil
73 "Procedure to send the string argument from the scheme process.")
74
75(defconst default-xscheme-runlight
76 '(": " xscheme-runlight-string)
77 "Default global (shared) xscheme-runlight modeline format.")
78
79(defvar xscheme-runlight "")
80(defvar xscheme-runlight-string nil)
81
82(defvar xscheme-process-filter-state 'idle
83 "State of scheme process escape reader state machine:
84idle waiting for an escape sequence
85reading-type received an altmode but nothing else
86reading-string reading prompt string")
87
88(defvar xscheme-allow-output-p t
89 "This variable, if nil, prevents output from the scheme process
90from being inserted into the process-buffer.")
91
92(defvar xscheme-prompt ""
93 "The current scheme prompt string.")
94
95(defvar xscheme-string-accumulator ""
96 "Accumulator for the string being received from the scheme process.")
97
98(defvar xscheme-mode-string nil)
99(setq-default scheme-mode-line-process
100 '("" xscheme-runlight))
101
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102(mapc 'make-variable-buffer-local
103 '(xscheme-expressions-ring
104 xscheme-expressions-ring-yank-pointer
105 xscheme-process-filter-state
106 xscheme-running-p
107 xscheme-control-g-disabled-p
108 xscheme-allow-output-p
109 xscheme-prompt
110 xscheme-string-accumulator
111 xscheme-mode-string
112 scheme-mode-line-process))
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113\f
114(defgroup xscheme nil
115 "Major mode for editing Scheme and interacting with MIT's C-Scheme."
116 :group 'lisp)
117
118(defcustom scheme-band-name nil
119 "*Band loaded by the `run-scheme' command."
120 :type '(choice (const nil) string)
121 :group 'xscheme)
122
123(defcustom scheme-program-arguments nil
124 "*Arguments passed to the Scheme program by the `run-scheme' command."
125 :type '(choice (const nil) string)
126 :group 'xscheme)
127
128(defcustom xscheme-allow-pipelined-evaluation t
129 "If non-nil, an expression may be transmitted while another is evaluating.
130Otherwise, attempting to evaluate an expression before the previous expression
131has finished evaluating will signal an error."
132 :type 'boolean
133 :group 'xscheme)
134
135(defcustom xscheme-startup-message
136 "This is the Scheme process buffer.
8cb95edf 137Type \\[xscheme-send-previous-expression] to evaluate the expression before point.
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138Type \\[xscheme-send-control-g-interrupt] to abort evaluation.
139Type \\[describe-mode] for more information.
140
141"
142 "String to insert into Scheme process buffer first time it is started.
143Is processed with `substitute-command-keys' first."
144 :type 'string
145 :group 'xscheme)
146
147(defcustom xscheme-signal-death-message nil
148 "If non-nil, causes a message to be generated when the Scheme process dies."
149 :type 'boolean
150 :group 'xscheme)
151
152(defcustom xscheme-start-hook nil
153 "If non-nil, a procedure to call when the Scheme process is started.
154When called, the current buffer will be the Scheme process-buffer."
155 :type 'hook
156 :group 'xscheme
157 :version "20.3")
158
159(defun xscheme-evaluation-commands (keymap)
160 (define-key keymap "\e\C-x" 'xscheme-send-definition)
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161 (define-key keymap "\C-x\C-e" 'xscheme-send-previous-expression)
162 (put 'xscheme-send-previous-expression :advertised-binding "\C-x\C-e")
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163 (define-key keymap "\eo" 'xscheme-send-buffer)
164 (define-key keymap "\ez" 'xscheme-send-definition)
165 (define-key keymap "\e\C-m" 'xscheme-send-previous-expression)
166 (define-key keymap "\e\C-z" 'xscheme-send-region))
167
168(defun xscheme-interrupt-commands (keymap)
169 (define-key keymap "\C-c\C-s" 'xscheme-select-process-buffer)
170 (define-key keymap "\C-c\C-b" 'xscheme-send-breakpoint-interrupt)
171 (define-key keymap "\C-c\C-c" 'xscheme-send-control-g-interrupt)
172 (define-key keymap "\C-c\C-u" 'xscheme-send-control-u-interrupt)
173 (define-key keymap "\C-c\C-x" 'xscheme-send-control-x-interrupt))
174
175(xscheme-evaluation-commands scheme-mode-map)
176(xscheme-interrupt-commands scheme-mode-map)
177\f
178(defun run-scheme (command-line)
179 "Run MIT Scheme in an inferior process.
180Output goes to the buffer `*scheme*'.
181With argument, asks for a command line."
182 (interactive (list (xscheme-read-command-line current-prefix-arg)))
183 (xscheme-start command-line xscheme-process-name xscheme-buffer-name))
184
185(defun xscheme-start (command-line process-name buffer-name)
186 (setq-default xscheme-process-command-line command-line)
187 (switch-to-buffer
188 (xscheme-start-process command-line process-name buffer-name))
189 (make-local-variable 'xscheme-process-command-line)
190 (setq xscheme-process-command-line command-line))
191
192(defun xscheme-read-command-line (arg)
193 (let ((default
194 (or xscheme-process-command-line
195 (xscheme-default-command-line))))
196 (if arg
197 (read-string "Run Scheme: " default)
198 default)))
199
200(defun xscheme-default-command-line ()
201 (concat scheme-program-name " -emacs"
202 (if scheme-program-arguments
203 (concat " " scheme-program-arguments)
204 "")
205 (if scheme-band-name
206 (concat " -band " scheme-band-name)
207 "")))
208
209(defun reset-scheme ()
210 "Reset the Scheme process."
211 (interactive)
212 (let ((process (get-process xscheme-process-name)))
213 (cond ((or (not process)
214 (not (eq (process-status process) 'run))
215 (yes-or-no-p
216"The Scheme process is running, are you SURE you want to reset it? "))
217 (message "Resetting Scheme process...")
218 (if process
219 (progn
220 (kill-process process t)
221 (delete-process process)))
222 (xscheme-start-process xscheme-process-command-line
223 xscheme-process-name
224 xscheme-buffer-name)
225 (message "Resetting Scheme process...done")))))
226\f
227;;;; Multiple Scheme buffer management commands
228
229(defun start-scheme (buffer-name &optional globally)
230 "Choose a scheme interaction buffer, or create a new one."
231 ;; (interactive "BScheme interaction buffer: \nP")
232 (interactive
233 (list (read-buffer "Scheme interaction buffer: "
234 xscheme-buffer-name
235 nil)
236 current-prefix-arg))
237 (let ((buffer (get-buffer-create buffer-name)))
238 (let ((process (get-buffer-process buffer)))
239 (if process
240 (switch-to-buffer buffer)
241 (if (or (not (buffer-file-name buffer))
242 (yes-or-no-p (concat "Buffer "
243 (buffer-name buffer)
244 " contains file "
245 (buffer-file-name buffer)
246 "; start scheme in it? ")))
247 (progn
248 (xscheme-start (xscheme-read-command-line t)
249 buffer-name
250 buffer-name)
251 (if globally
252 (global-set-scheme-interaction-buffer buffer-name)))
253 (message "start-scheme aborted"))))))
254
255(fset 'select-scheme 'start-scheme)
256
257(defun global-set-scheme-interaction-buffer (buffer-name)
258 "Set the default scheme interaction buffer."
259 (interactive
260 (list (read-buffer "Scheme interaction buffer: "
261 xscheme-buffer-name
262 t)))
263 (let ((process-name (verify-xscheme-buffer buffer-name nil)))
264 (setq-default xscheme-buffer-name buffer-name)
265 (setq-default xscheme-process-name process-name)
266 (setq-default xscheme-runlight-string
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267 (with-current-buffer buffer-name
268 xscheme-runlight-string))
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269 (setq-default xscheme-runlight
270 (if (eq (process-status process-name) 'run)
271 default-xscheme-runlight
272 ""))))
273
274(defun local-set-scheme-interaction-buffer (buffer-name)
275 "Set the scheme interaction buffer for the current buffer."
276 (interactive
277 (list (read-buffer "Scheme interaction buffer: "
278 xscheme-buffer-name
279 t)))
280 (let ((process-name (verify-xscheme-buffer buffer-name t)))
281 (make-local-variable 'xscheme-buffer-name)
282 (setq xscheme-buffer-name buffer-name)
283 (make-local-variable 'xscheme-process-name)
284 (setq xscheme-process-name process-name)
285 (make-local-variable 'xscheme-runlight)
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286 (setq xscheme-runlight (with-current-buffer buffer-name
287 xscheme-runlight))))
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288
289(defun local-clear-scheme-interaction-buffer ()
290 "Make the current buffer use the default scheme interaction buffer."
291 (interactive)
292 (if (xscheme-process-buffer-current-p)
293 (error "Cannot change the interaction buffer of an interaction buffer"))
294 (kill-local-variable 'xscheme-buffer-name)
295 (kill-local-variable 'xscheme-process-name)
296 (kill-local-variable 'xscheme-runlight))
297
298(defun verify-xscheme-buffer (buffer-name localp)
299 (if (and localp (xscheme-process-buffer-current-p))
300 (error "Cannot change the interaction buffer of an interaction buffer"))
301 (let* ((buffer (get-buffer buffer-name))
302 (process (and buffer (get-buffer-process buffer))))
303 (cond ((not buffer)
ac72d80b 304 (error "Buffer `%s' does not exist" buffer-name))
c5c3d778 305 ((not process)
ac72d80b 306 (error "Buffer `%s' is not a scheme interaction buffer" buffer-name))
c5c3d778 307 (t
9a529312 308 (with-current-buffer buffer
c5c3d778 309 (if (not (xscheme-process-buffer-current-p))
ac72d80b 310 (error "Buffer `%s' is not a scheme interaction buffer"
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311 buffer-name)))
312 (process-name process)))))
313\f
314;;;; Interaction Mode
315
316(defun scheme-interaction-mode (&optional preserve)
317 "Major mode for interacting with an inferior MIT Scheme process.
318Like scheme-mode except that:
319
8cb95edf 320\\[xscheme-send-previous-expression] sends the expression before point to the Scheme process as input
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321\\[xscheme-yank-pop] yanks an expression previously sent to Scheme
322\\[xscheme-yank-push] yanks an expression more recently sent to Scheme
323
324All output from the Scheme process is written in the Scheme process
325buffer, which is initially named \"*scheme*\". The result of
326evaluating a Scheme expression is also printed in the process buffer,
327preceded by the string \";Value: \" to highlight it. If the process
328buffer is not visible at that time, the value will also be displayed
329in the minibuffer. If an error occurs, the process buffer will
330automatically pop up to show you the error message.
331
332While the Scheme process is running, the modelines of all buffers in
333scheme-mode are modified to show the state of the process. The
334possible states and their meanings are:
335
336input waiting for input
337run evaluating
338gc garbage collecting
339
340The process buffer's modeline contains additional information where
341the buffer's name is normally displayed: the command interpreter level
342and type.
343
344Scheme maintains a stack of command interpreters. Every time an error
345or breakpoint occurs, the current command interpreter is pushed on the
346command interpreter stack, and a new command interpreter is started.
347One example of why this is done is so that an error that occurs while
348you are debugging another error will not destroy the state of the
349initial error, allowing you to return to it after the second error has
350been fixed.
351
352The command interpreter level indicates how many interpreters are in
353the command interpreter stack. It is initially set to one, and it is
354incremented every time that stack is pushed, and decremented every
355time it is popped. The following commands are useful for manipulating
356the command interpreter stack:
357
358\\[xscheme-send-breakpoint-interrupt] pushes the stack once
359\\[xscheme-send-control-u-interrupt] pops the stack once
360\\[xscheme-send-control-g-interrupt] pops everything off
361\\[xscheme-send-control-x-interrupt] aborts evaluation, doesn't affect stack
362
363Some possible command interpreter types and their meanings are:
364
365\[Evaluator] read-eval-print loop for evaluating expressions
366\[Debugger] single character commands for debugging errors
367\[Where] single character commands for examining environments
368
369Starting with release 6.2 of Scheme, the latter two types of command
370interpreters will change the major mode of the Scheme process buffer
371to scheme-debugger-mode , in which the evaluation commands are
372disabled, and the keys which normally self insert instead send
373themselves to the Scheme process. The command character ? will list
374the available commands.
375
376For older releases of Scheme, the major mode will be be
377scheme-interaction-mode , and the command characters must be sent as
378if they were expressions.
379
380Commands:
381Delete converts tabs to spaces as it moves back.
382Blank lines separate paragraphs. Semicolons start comments.
383\\{scheme-interaction-mode-map}
384
385Entry to this mode calls the value of scheme-interaction-mode-hook
386with no args, if that value is non-nil.
387 Likewise with the value of scheme-mode-hook.
388 scheme-interaction-mode-hook is called after scheme-mode-hook."
389 (interactive "P")
390 (if (not preserve)
391 (let ((previous-mode major-mode))
392 (kill-all-local-variables)
393 (make-local-variable 'xscheme-previous-mode)
394 (make-local-variable 'xscheme-buffer-name)
395 (make-local-variable 'xscheme-process-name)
396 (make-local-variable 'xscheme-previous-process-state)
397 (make-local-variable 'xscheme-runlight-string)
398 (make-local-variable 'xscheme-runlight)
399 (make-local-variable 'xscheme-last-input-end)
400 (setq xscheme-previous-mode previous-mode)
401 (let ((buffer (current-buffer)))
402 (setq xscheme-buffer-name (buffer-name buffer))
403 (setq xscheme-last-input-end (make-marker))
404 (let ((process (get-buffer-process buffer)))
405 (if process
406 (progn
407 (setq xscheme-process-name (process-name process))
408 (setq xscheme-previous-process-state
409 (cons (process-filter process)
410 (process-sentinel process)))
411 (xscheme-process-filter-initialize t)
412 (xscheme-modeline-initialize xscheme-buffer-name)
413 (set-process-sentinel process 'xscheme-process-sentinel)
414 (set-process-filter process 'xscheme-process-filter))
415 (setq xscheme-previous-process-state (cons nil nil)))))))
416 (scheme-interaction-mode-initialize)
417 (scheme-mode-variables)
9a969196 418 (run-mode-hooks 'scheme-mode-hook 'scheme-interaction-mode-hook))
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419
420(defun exit-scheme-interaction-mode ()
421 "Take buffer out of scheme interaction mode"
422 (interactive)
423 (if (not (eq major-mode 'scheme-interaction-mode))
424 (error "Buffer not in scheme interaction mode"))
425 (let ((previous-state xscheme-previous-process-state))
426 (funcall xscheme-previous-mode)
427 (let ((process (get-buffer-process (current-buffer))))
428 (if process
429 (progn
430 (if (eq (process-filter process) 'xscheme-process-filter)
431 (set-process-filter process (car previous-state)))
432 (if (eq (process-sentinel process) 'xscheme-process-sentinel)
433 (set-process-sentinel process (cdr previous-state))))))))
434
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435(defvar scheme-interaction-mode-commands-alist nil)
436(defvar scheme-interaction-mode-map nil)
437
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438(defun scheme-interaction-mode-initialize ()
439 (use-local-map scheme-interaction-mode-map)
440 (setq major-mode 'scheme-interaction-mode)
441 (setq mode-name "Scheme Interaction"))
442
443(defun scheme-interaction-mode-commands (keymap)
444 (let ((entries scheme-interaction-mode-commands-alist))
445 (while entries
446 (define-key keymap
447 (car (car entries))
448 (car (cdr (car entries))))
449 (setq entries (cdr entries)))))
450
f28d4b0f 451;; Initialize the command alist
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452(setq scheme-interaction-mode-commands-alist
453 (append scheme-interaction-mode-commands-alist
454 '(("\C-c\C-m" xscheme-send-current-line)
455 ("\C-c\C-o" xscheme-delete-output)
456 ("\C-c\C-p" xscheme-send-proceed)
457 ("\C-c\C-y" xscheme-yank)
458 ("\ep" xscheme-yank-pop)
459 ("\en" xscheme-yank-push))))
460
f28d4b0f 461;; Initialize the mode map
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462(if (not scheme-interaction-mode-map)
463 (progn
464 (setq scheme-interaction-mode-map (make-keymap))
465 (scheme-mode-commands scheme-interaction-mode-map)
466 (xscheme-interrupt-commands scheme-interaction-mode-map)
467 (xscheme-evaluation-commands scheme-interaction-mode-map)
468 (scheme-interaction-mode-commands scheme-interaction-mode-map)))
469
470(defun xscheme-enter-interaction-mode ()
9a529312 471 (with-current-buffer (xscheme-process-buffer)
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472 (if (not (eq major-mode 'scheme-interaction-mode))
473 (if (eq major-mode 'scheme-debugger-mode)
474 (scheme-interaction-mode-initialize)
475 (scheme-interaction-mode t)))))
476
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477(define-obsolete-function-alias 'advertised-xscheme-send-previous-expression
478 'xscheme-send-previous-expression "23.2")
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479\f
480;;;; Debugger Mode
481
482(defun scheme-debugger-mode ()
483 "Major mode for executing the Scheme debugger.
484Like scheme-mode except that the evaluation commands
485are disabled, and characters that would normally be self inserting are
486sent to the Scheme process instead. Typing ? will show you which
487characters perform useful functions.
488
489Commands:
490\\{scheme-debugger-mode-map}"
eac9c0ef 491 (error "Invalid entry to scheme-debugger-mode"))
c5c3d778 492
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493(defvar scheme-debugger-mode-map nil)
494
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495(defun scheme-debugger-mode-initialize ()
496 (use-local-map scheme-debugger-mode-map)
497 (setq major-mode 'scheme-debugger-mode)
498 (setq mode-name "Scheme Debugger"))
499
500(defun scheme-debugger-mode-commands (keymap)
f28d4b0f 501 (let ((char ?\s))
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502 (while (< char 127)
503 (define-key keymap (char-to-string char) 'scheme-debugger-self-insert)
504 (setq char (1+ char)))))
505
f28d4b0f 506;; Initialize the debugger mode map
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507(if (not scheme-debugger-mode-map)
508 (progn
509 (setq scheme-debugger-mode-map (make-keymap))
510 (scheme-mode-commands scheme-debugger-mode-map)
511 (xscheme-interrupt-commands scheme-debugger-mode-map)
512 (scheme-debugger-mode-commands scheme-debugger-mode-map)))
513
514(defun scheme-debugger-self-insert ()
515 "Transmit this character to the Scheme process."
516 (interactive)
1ba983e8 517 (xscheme-send-char last-command-event))
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518
519(defun xscheme-enter-debugger-mode (prompt-string)
9a529312 520 (with-current-buffer (xscheme-process-buffer)
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521 (if (not (eq major-mode 'scheme-debugger-mode))
522 (progn
523 (if (not (eq major-mode 'scheme-interaction-mode))
524 (scheme-interaction-mode t))
525 (scheme-debugger-mode-initialize)))))
526
527(defun xscheme-debugger-mode-p ()
528 (let ((buffer (xscheme-process-buffer)))
529 (and buffer
9a529312 530 (with-current-buffer buffer
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531 (eq major-mode 'scheme-debugger-mode)))))
532\f
533;;;; Evaluation Commands
534
535(defun xscheme-send-string (&rest strings)
536 "Send the string arguments to the Scheme process.
537The strings are concatenated and terminated by a newline."
538 (cond ((not (xscheme-process-running-p))
539 (if (yes-or-no-p "The Scheme process has died. Reset it? ")
540 (progn
541 (reset-scheme)
542 (xscheme-wait-for-process)
543 (xscheme-send-string-1 strings))))
544 ((xscheme-debugger-mode-p) (error "No sends allowed in debugger mode"))
545 ((and (not xscheme-allow-pipelined-evaluation)
546 xscheme-running-p)
547 (error "No sends allowed while Scheme running"))
548 (t (xscheme-send-string-1 strings))))
549
550(defun xscheme-send-string-1 (strings)
551 (let ((string (apply 'concat strings)))
552 (xscheme-send-string-2 string)
553 (if (eq major-mode 'scheme-interaction-mode)
554 (xscheme-insert-expression string))))
555
556(defun xscheme-send-string-2 (string)
557 (let ((process (get-process xscheme-process-name)))
558 (process-send-string process (concat string "\n"))
559 (if (xscheme-process-buffer-current-p)
560 (set-marker (process-mark process) (point)))))
561
562(defun xscheme-select-process-buffer ()
563 "Select the Scheme process buffer and move to its output point."
564 (interactive)
565 (let ((process
566 (or (get-process xscheme-process-name)
567 (error "No scheme process"))))
568 (let ((buffer (or (process-buffer process) (error "No process buffer"))))
569 (let ((window (get-buffer-window buffer)))
570 (if window
571 (select-window window)
572 (switch-to-buffer buffer))
573 (goto-char (process-mark process))))))
574\f
575;;;; Scheme expressions ring
576
577(defun xscheme-insert-expression (string)
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578 (setq xscheme-expressions-ring-yank-pointer
579 (add-to-history 'xscheme-expressions-ring string
580 xscheme-expressions-ring-max)))
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581
582(defun xscheme-rotate-yank-pointer (arg)
583 "Rotate the yanking point in the kill ring."
584 (interactive "p")
585 (let ((length (length xscheme-expressions-ring)))
586 (if (zerop length)
587 (error "Scheme expression ring is empty")
588 (setq xscheme-expressions-ring-yank-pointer
589 (let ((index
590 (% (+ arg
591 (- length
592 (length xscheme-expressions-ring-yank-pointer)))
593 length)))
594 (nthcdr (if (< index 0)
595 (+ index length)
596 index)
597 xscheme-expressions-ring))))))
598
599(defun xscheme-yank (&optional arg)
600 "Insert the most recent expression at point.
601With just C-U as argument, same but put point in front (and mark at end).
602With argument n, reinsert the nth most recently sent expression.
603See also the commands \\[xscheme-yank-pop] and \\[xscheme-yank-push]."
604 (interactive "*P")
605 (xscheme-rotate-yank-pointer (if (listp arg) 0
606 (if (eq arg '-) -1
607 (1- arg))))
608 (push-mark (point))
609 (insert (car xscheme-expressions-ring-yank-pointer))
610 (if (consp arg)
611 (exchange-point-and-mark)))
612
613;; Old name, to avoid errors in users' init files.
614(fset 'xscheme-yank-previous-send
615 'xscheme-yank)
616
617(defun xscheme-yank-pop (arg)
618 "Insert or replace a just-yanked expression with an older expression.
619If the previous command was not a yank, it yanks.
620Otherwise, the region contains a stretch of reinserted
621expression. yank-pop deletes that text and inserts in its
622place a different expression.
623
624With no argument, the next older expression is inserted.
625With argument n, the n'th older expression is inserted.
626If n is negative, this is a more recent expression.
627
628The sequence of expressions wraps around, so that after the oldest one
629comes the newest one."
630 (interactive "*p")
631 (setq this-command 'xscheme-yank)
632 (if (not (eq last-command 'xscheme-yank))
633 (progn
634 (xscheme-yank)
635 (setq arg (- arg 1))))
636 (if (not (= arg 0))
637 (let ((before (< (point) (mark))))
638 (delete-region (point) (mark))
639 (xscheme-rotate-yank-pointer arg)
640 (set-mark (point))
641 (insert (car xscheme-expressions-ring-yank-pointer))
642 (if before (exchange-point-and-mark)))))
643
644(defun xscheme-yank-push (arg)
645 "Insert or replace a just-yanked expression with a more recent expression.
646If the previous command was not a yank, it yanks.
647Otherwise, the region contains a stretch of reinserted
648expression. yank-pop deletes that text and inserts in its
649place a different expression.
650
651With no argument, the next more recent expression is inserted.
652With argument n, the n'th more recent expression is inserted.
653If n is negative, a less recent expression is used.
654
655The sequence of expressions wraps around, so that after the oldest one
656comes the newest one."
657 (interactive "*p")
658 (xscheme-yank-pop (- 0 arg)))
659\f
660(defun xscheme-send-region (start end)
661 "Send the current region to the Scheme process.
662The region is sent terminated by a newline."
663 (interactive "r")
664 (if (xscheme-process-buffer-current-p)
665 (progn
666 (goto-char end)
667 (if (not (bolp))
668 (insert-before-markers ?\n))
669 (set-marker (process-mark (get-process xscheme-process-name))
670 (point))
671 (set-marker xscheme-last-input-end (point))))
672 (xscheme-send-string (buffer-substring start end)))
673
674(defun xscheme-send-definition ()
675 "Send the current definition to the Scheme process.
676If the current line begins with a non-whitespace character,
677parse an expression from the beginning of the line and send that instead."
678 (interactive)
679 (let ((start nil) (end nil))
680 (save-excursion
681 (end-of-defun)
682 (setq end (point))
683 (if (re-search-backward "^\\s(" nil t)
684 (setq start (point))
685 (error "Can't find definition")))
686 (xscheme-send-region start end)))
687
688(defun xscheme-send-next-expression ()
689 "Send the expression to the right of `point' to the Scheme process."
690 (interactive)
691 (let ((start (point)))
692 (xscheme-send-region start (save-excursion (forward-sexp) (point)))))
693
694(defun xscheme-send-previous-expression ()
695 "Send the expression to the left of `point' to the Scheme process."
696 (interactive)
697 (let ((end (point)))
698 (xscheme-send-region (save-excursion (backward-sexp) (point)) end)))
699\f
700(defun xscheme-send-current-line ()
701 "Send the current line to the Scheme process.
702Useful for working with debugging Scheme under adb."
703 (interactive)
704 (let ((line
705 (save-excursion
706 (beginning-of-line)
707 (let ((start (point)))
708 (end-of-line)
709 (buffer-substring start (point))))))
710 (end-of-line)
711 (insert ?\n)
712 (xscheme-send-string-2 line)))
713
714(defun xscheme-send-buffer ()
715 "Send the current buffer to the Scheme process."
716 (interactive)
717 (if (xscheme-process-buffer-current-p)
718 (error "Not allowed to send this buffer's contents to Scheme"))
719 (xscheme-send-region (point-min) (point-max)))
720
721(defun xscheme-send-char (char)
722 "Prompt for a character and send it to the Scheme process."
723 (interactive "cCharacter to send: ")
724 (process-send-string xscheme-process-name (char-to-string char)))
725
726(defun xscheme-delete-output ()
727 "Delete all output from interpreter since last input."
728 (interactive)
729 (let ((proc (get-buffer-process (current-buffer))))
730 (save-excursion
731 (goto-char (process-mark proc))
732 (re-search-backward
733 "^;\\(Unspecified return value$\\|Value\\( [0-9]+\\)?: \\|\\(Abort\\|Up\\|Quit\\)!$\\)"
734 xscheme-last-input-end
735 t)
736 (forward-line 0)
737 (if (< (marker-position xscheme-last-input-end) (point))
738 (progn
739 (delete-region xscheme-last-input-end (point))
740 (insert-before-markers "*** output flushed ***\n"))))))
741\f
742;;;; Interrupts
743
744(defun xscheme-send-breakpoint-interrupt ()
745 "Cause the Scheme process to enter a breakpoint."
746 (interactive)
747 (xscheme-send-interrupt ?b nil))
748
749(defun xscheme-send-proceed ()
750 "Cause the Scheme process to proceed from a breakpoint."
751 (interactive)
752 (process-send-string xscheme-process-name "(proceed)\n"))
753
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754(defconst xscheme-control-g-message-string
755 "Sending C-G interrupt to Scheme...")
756
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757(defun xscheme-send-control-g-interrupt ()
758 "Cause the Scheme processor to halt and flush input.
759Control returns to the top level rep loop."
760 (interactive)
761 (let ((inhibit-quit t))
762 (cond ((not xscheme-control-g-synchronization-p)
763 (interrupt-process xscheme-process-name))
9a529312 764 ((with-current-buffer xscheme-buffer-name
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765 xscheme-control-g-disabled-p)
766 (message "Relax..."))
767 (t
9a529312 768 (with-current-buffer xscheme-buffer-name
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769 (setq xscheme-control-g-disabled-p t))
770 (message xscheme-control-g-message-string)
771 (interrupt-process xscheme-process-name)
772 (sleep-for 0.1)
773 (xscheme-send-char 0)))))
774
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775(defun xscheme-send-control-u-interrupt ()
776 "Cause the Scheme process to halt, returning to previous rep loop."
777 (interactive)
778 (xscheme-send-interrupt ?u t))
779
780(defun xscheme-send-control-x-interrupt ()
781 "Cause the Scheme process to halt, returning to current rep loop."
782 (interactive)
783 (xscheme-send-interrupt ?x t))
784
785;;; This doesn't really work right -- Scheme just gobbles the first
786;;; character in the input. There is no way for us to guarantee that
787;;; the argument to this procedure is the first char unless we put
788;;; some kind of marker in the input stream.
789
790(defun xscheme-send-interrupt (char mark-p)
791 "Send a ^A type interrupt to the Scheme process."
792 (interactive "cInterrupt character to send: ")
793 (quit-process xscheme-process-name)
794 (sleep-for 0.1)
795 (xscheme-send-char char)
796 (if (and mark-p xscheme-control-g-synchronization-p)
797 (xscheme-send-char 0)))
798\f
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799;;;; Basic Process Control
800
801(defun xscheme-start-process (command-line the-process the-buffer)
802 (let ((buffer (get-buffer-create the-buffer)))
803 (let ((process (get-buffer-process buffer)))
9a529312 804 (with-current-buffer buffer
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805 (if (and process (memq (process-status process) '(run stop)))
806 (set-marker (process-mark process) (point-max))
807 (progn (if process (delete-process process))
808 (goto-char (point-max))
809 (scheme-interaction-mode nil)
810 (setq xscheme-process-name the-process)
811 (if (bobp)
812 (insert-before-markers
813 (substitute-command-keys xscheme-startup-message)))
814 (setq process
815 (let ((process-connection-type nil))
816 (apply 'start-process
817 (cons the-process
818 (cons buffer
819 (xscheme-parse-command-line
820 command-line))))))
821 (if (not (equal (process-name process) the-process))
822 (setq xscheme-process-name (process-name process)))
823 (if (not (equal (buffer-name buffer) the-buffer))
824 (setq xscheme-buffer-name (buffer-name buffer)))
825 (message "Starting process %s in buffer %s"
826 xscheme-process-name
827 xscheme-buffer-name)
828 (set-marker (process-mark process) (point-max))
829 (xscheme-process-filter-initialize t)
830 (xscheme-modeline-initialize xscheme-buffer-name)
831 (set-process-sentinel process 'xscheme-process-sentinel)
832 (set-process-filter process 'xscheme-process-filter)
833 (run-hooks 'xscheme-start-hook)))))
834 buffer))
835
836(defun xscheme-parse-command-line (string)
837 (setq string (substitute-in-file-name string))
838 (let ((start 0)
839 (result '()))
840 (while start
841 (let ((index (string-match "[ \t]" string start)))
842 (setq start
843 (cond ((not index)
844 (setq result
845 (cons (substring string start)
846 result))
847 nil)
848 ((= index start)
849 (string-match "[^ \t]" string start))
850 (t
851 (setq result
852 (cons (substring string start index)
853 result))
854 (1+ index))))))
855 (nreverse result)))
856\f
857(defun xscheme-wait-for-process ()
858 (sleep-for 2)
859 (while xscheme-running-p
860 (sleep-for 1)))
861
862(defun xscheme-process-running-p ()
e7f767c2 863 "True if there is a Scheme process whose status is `run'."
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864 (let ((process (get-process xscheme-process-name)))
865 (and process
866 (eq (process-status process) 'run))))
867
868(defun xscheme-process-buffer ()
869 (let ((process (get-process xscheme-process-name)))
870 (and process (process-buffer process))))
871
872(defun xscheme-process-buffer-window ()
873 (let ((buffer (xscheme-process-buffer)))
874 (and buffer (get-buffer-window buffer))))
875
876(defun xscheme-process-buffer-current-p ()
e7f767c2 877 "True if the current buffer is the Scheme process buffer."
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878 (eq (xscheme-process-buffer) (current-buffer)))
879\f
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880;;;; Process Filter Operations
881
882(defvar xscheme-process-filter-alist
883 '((?A xscheme-eval
884 xscheme-process-filter:string-action-noexcursion)
885 (?D xscheme-enter-debugger-mode
886 xscheme-process-filter:string-action)
887 (?E xscheme-eval
888 xscheme-process-filter:string-action)
889 (?P xscheme-set-prompt-variable
890 xscheme-process-filter:string-action)
891 (?R xscheme-enter-interaction-mode
892 xscheme-process-filter:simple-action)
893 (?b xscheme-start-gc
894 xscheme-process-filter:simple-action)
895 (?c xscheme-unsolicited-read-char
896 xscheme-process-filter:simple-action)
897 (?e xscheme-finish-gc
898 xscheme-process-filter:simple-action)
899 (?f xscheme-exit-input-wait
900 xscheme-process-filter:simple-action)
901 (?g xscheme-enable-control-g
902 xscheme-process-filter:simple-action)
903 (?i xscheme-prompt-for-expression
904 xscheme-process-filter:string-action)
905 (?m xscheme-message
906 xscheme-process-filter:string-action)
907 (?n xscheme-prompt-for-confirmation
908 xscheme-process-filter:string-action)
909 (?o xscheme-output-goto
910 xscheme-process-filter:simple-action)
911 (?p xscheme-set-prompt
912 xscheme-process-filter:string-action)
913 (?s xscheme-enter-input-wait
914 xscheme-process-filter:simple-action)
915 (?v xscheme-write-value
916 xscheme-process-filter:string-action)
917 (?w xscheme-cd
918 xscheme-process-filter:string-action)
919 (?z xscheme-display-process-buffer
920 xscheme-process-filter:simple-action))
921 "Table used to decide how to handle process filter commands.
922Value is a list of entries, each entry is a list of three items.
923
924The first item is the character that the process filter dispatches on.
925The second item is the action to be taken, a function.
926The third item is the handler for the entry, a function.
927
928When the process filter sees a command whose character matches a
929particular entry, it calls the handler with two arguments: the action
930and the string containing the rest of the process filter's input
931stream. It is the responsibility of the handler to invoke the action
932with the appropriate arguments, and to reenter the process filter with
933the remaining input.")
934\f
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935;;;; Process Filter
936
937(defun xscheme-process-sentinel (proc reason)
938 (let* ((buffer (process-buffer proc))
939 (name (buffer-name buffer)))
9a529312 940 (with-current-buffer buffer
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941 (xscheme-process-filter-initialize (eq reason 'run))
942 (if (not (eq reason 'run))
943 (progn
944 (setq scheme-mode-line-process "")
945 (setq xscheme-mode-string "no process")
946 (if (equal name (default-value 'xscheme-buffer-name))
947 (setq-default xscheme-runlight ""))))
948 (if (and (not (memq reason '(run stop)))
949 xscheme-signal-death-message)
950 (progn
951 (beep)
952 (message
953"The Scheme process has died! Do M-x reset-scheme to restart it"))))))
954
955(defun xscheme-process-filter-initialize (running-p)
956 (setq xscheme-process-filter-state 'idle)
957 (setq xscheme-running-p running-p)
958 (setq xscheme-control-g-disabled-p nil)
959 (setq xscheme-allow-output-p t)
960 (setq xscheme-prompt "")
961 (if running-p
962 (let ((name (buffer-name (current-buffer))))
963 (setq scheme-mode-line-process '(": " xscheme-runlight-string))
964 (xscheme-modeline-initialize name)
965 (if (equal name (default-value 'xscheme-buffer-name))
966 (setq-default xscheme-runlight default-xscheme-runlight))))
967 (if (or (eq xscheme-runlight default-xscheme-runlight)
968 (equal xscheme-runlight ""))
969 (setq xscheme-runlight (list ": " 'xscheme-buffer-name ": " "?")))
970 (rplaca (nthcdr 3 xscheme-runlight)
971 (if running-p "?" "no process")))
972
973(defun xscheme-process-filter (proc string)
974 (let ((xscheme-filter-input string)
975 (call-noexcursion nil))
976 (while xscheme-filter-input
977 (setq call-noexcursion nil)
9a529312 978 (with-current-buffer (process-buffer proc)
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979 (cond ((eq xscheme-process-filter-state 'idle)
980 (let ((start (string-match "\e" xscheme-filter-input)))
981 (if start
982 (progn
983 (xscheme-process-filter-output
984 (substring xscheme-filter-input 0 start))
985 (setq xscheme-filter-input
986 (substring xscheme-filter-input (1+ start)))
987 (setq xscheme-process-filter-state 'reading-type))
988 (let ((string xscheme-filter-input))
989 (setq xscheme-filter-input nil)
990 (xscheme-process-filter-output string)))))
991 ((eq xscheme-process-filter-state 'reading-type)
992 (if (zerop (length xscheme-filter-input))
993 (setq xscheme-filter-input nil)
994 (let ((char (aref xscheme-filter-input 0)))
995 (setq xscheme-filter-input
996 (substring xscheme-filter-input 1))
997 (let ((entry (assoc char xscheme-process-filter-alist)))
998 (if entry
999 (funcall (nth 2 entry) (nth 1 entry))
1000 (progn
1001 (xscheme-process-filter-output ?\e char)
1002 (setq xscheme-process-filter-state 'idle)))))))
1003 ((eq xscheme-process-filter-state 'reading-string)
1004 (let ((start (string-match "\e" xscheme-filter-input)))
1005 (if start
1006 (let ((string
1007 (concat xscheme-string-accumulator
1008 (substring xscheme-filter-input 0 start))))
1009 (setq xscheme-filter-input
1010 (substring xscheme-filter-input (1+ start)))
1011 (setq xscheme-process-filter-state 'idle)
1012 (if (listp xscheme-string-receiver)
1013 (progn
1014 (setq xscheme-string-receiver
1015 (car xscheme-string-receiver))
1016 (setq call-noexcursion string))
1017 (funcall xscheme-string-receiver string)))
1018 (progn
1019 (setq xscheme-string-accumulator
1020 (concat xscheme-string-accumulator
1021 xscheme-filter-input))
1022 (setq xscheme-filter-input nil)))))
1023 (t
1024 (error "Scheme process filter -- bad state"))))
1025 (if call-noexcursion
1026 (funcall xscheme-string-receiver call-noexcursion)))))
1027\f
1028;;;; Process Filter Output
1029
1030(defun xscheme-process-filter-output (&rest args)
1031 (if xscheme-allow-output-p
1032 (let ((string (apply 'concat args)))
1033 (save-excursion
1034 (xscheme-goto-output-point)
1035 (let ((old-point (point)))
1036 (while (string-match "\\(\007\\|\f\\)" string)
1037 (let ((start (match-beginning 0))
1038 (end (match-end 0)))
1039 (insert-before-markers (substring string 0 start))
1040 (if (= ?\f (aref string start))
1041 (progn
1042 (if (not (bolp))
1043 (insert-before-markers ?\n))
1044 (insert-before-markers ?\f))
1045 (beep))
1046 (setq string (substring string (1+ start)))))
1047 (insert-before-markers string)
1048 (if (and xscheme-last-input-end
1049 (equal (marker-position xscheme-last-input-end) (point)))
1050 (set-marker xscheme-last-input-end old-point)))))))
1051
1052(defun xscheme-guarantee-newlines (n)
1053 (if xscheme-allow-output-p
1054 (save-excursion
1055 (xscheme-goto-output-point)
1056 (let ((stop nil))
1057 (while (and (not stop)
1058 (bolp))
1059 (setq n (1- n))
1060 (if (bobp)
1061 (setq stop t)
1062 (backward-char))))
1063 (xscheme-goto-output-point)
1064 (while (> n 0)
1065 (insert-before-markers ?\n)
1066 (setq n (1- n))))))
1067
1068(defun xscheme-goto-output-point ()
1069 (let ((process (get-process xscheme-process-name)))
1070 (set-buffer (process-buffer process))
1071 (goto-char (process-mark process))))
1072
1073(defun xscheme-modeline-initialize (name)
1074 (setq xscheme-runlight-string "")
1075 (if (equal name (default-value 'xscheme-buffer-name))
1076 (setq-default xscheme-runlight-string ""))
1077 (setq xscheme-mode-string "")
1078 (setq mode-line-buffer-identification
1079 (list (concat name ": ")
1080 'xscheme-mode-string)))
1081
1082(defun xscheme-set-runlight (runlight)
1083 (setq xscheme-runlight-string runlight)
1084 (if (equal (buffer-name (current-buffer))
1085 (default-value 'xscheme-buffer-name))
1086 (setq-default xscheme-runlight-string runlight))
1087 (rplaca (nthcdr 3 xscheme-runlight) runlight)
1088 (force-mode-line-update t))
1089\f
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1090(defun xscheme-process-filter:simple-action (action)
1091 (setq xscheme-process-filter-state 'idle)
1092 (funcall action))
1093
1094(defun xscheme-process-filter:string-action (action)
1095 (setq xscheme-string-receiver action)
1096 (setq xscheme-string-accumulator "")
1097 (setq xscheme-process-filter-state 'reading-string))
1098
1099(defun xscheme-process-filter:string-action-noexcursion (action)
1100 (xscheme-process-filter:string-action (cons action nil)))
1101
1102(defconst xscheme-runlight:running "run"
1103 "The character displayed when the Scheme process is running.")
1104
1105(defconst xscheme-runlight:input "input"
1106 "The character displayed when the Scheme process is waiting for input.")
1107
1108(defconst xscheme-runlight:gc "gc"
1109 "The character displayed when the Scheme process is garbage collecting.")
1110
1111(defun xscheme-start-gc ()
1112 (xscheme-set-runlight xscheme-runlight:gc))
1113
1114(defun xscheme-finish-gc ()
1115 (xscheme-set-runlight
1116 (if xscheme-running-p xscheme-runlight:running xscheme-runlight:input)))
1117
1118(defun xscheme-enter-input-wait ()
1119 (xscheme-set-runlight xscheme-runlight:input)
1120 (setq xscheme-control-g-disabled-p nil)
1121 (setq xscheme-running-p nil))
1122
1123(defun xscheme-exit-input-wait ()
1124 (xscheme-set-runlight xscheme-runlight:running)
1125 (setq xscheme-running-p t))
1126
1127(defun xscheme-enable-control-g ()
1128 (setq xscheme-control-g-disabled-p nil)
1129 (if (string= (current-message) xscheme-control-g-message-string)
1130 (message nil)))
1131
1132(defun xscheme-display-process-buffer ()
1133 (let ((window (or (xscheme-process-buffer-window)
1134 (display-buffer (xscheme-process-buffer)))))
1135 (save-window-excursion
1136 (select-window window)
1137 (xscheme-goto-output-point)
1138 (if (xscheme-debugger-mode-p)
1139 (xscheme-enter-interaction-mode)))))
1140
1141(defun xscheme-unsolicited-read-char ()
1142 nil)
1143\f
1144(defun xscheme-eval (string)
1145 (eval (car (read-from-string string))))
1146
1147(defun xscheme-message (string)
1148 (if (not (zerop (length string)))
1149 (xscheme-write-message-1 string (format ";%s" string))))
1150
1151(defun xscheme-write-value (string)
1152 (if (zerop (length string))
1153 (xscheme-write-message-1 "(no value)" ";Unspecified return value")
1154 (xscheme-write-message-1 string (format ";Value: %s" string))))
1155
1156(defun xscheme-write-message-1 (message-string output-string)
1157 (let* ((process (get-process xscheme-process-name))
1158 (window (get-buffer-window (process-buffer process))))
1159 (if (or (not window)
1160 (not (pos-visible-in-window-p (process-mark process)
1161 window)))
1162 (message "%s" message-string)))
1163 (xscheme-guarantee-newlines 1)
1164 (xscheme-process-filter-output output-string))
1165
1166(defun xscheme-set-prompt-variable (string)
1167 (setq xscheme-prompt string))
1168
1169(defun xscheme-set-prompt (string)
1170 (setq xscheme-prompt string)
1171 (xscheme-guarantee-newlines 2)
1172 (setq xscheme-mode-string (xscheme-coerce-prompt string))
1173 (force-mode-line-update t))
1174
1175(defun xscheme-output-goto ()
1176 (xscheme-goto-output-point)
1177 (xscheme-guarantee-newlines 2))
1178
1179(defun xscheme-coerce-prompt (string)
1180 (if (string-match "^[0-9]+ \\[[^]]+\\] " string)
1181 (let ((end (match-end 0)))
1182 (xscheme-process-filter-output (substring string end))
1183 (substring string 0 (- end 1)))
1184 string))
1185
1186(defun xscheme-cd (directory-string)
9a529312 1187 (with-current-buffer (xscheme-process-buffer)
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1188 (cd directory-string)))
1189\f
1190(defun xscheme-prompt-for-confirmation (prompt-string)
1191 (xscheme-send-char (if (y-or-n-p prompt-string) ?y ?n)))
1192
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1193(defvar xscheme-prompt-for-expression-map nil)
1194(if (not xscheme-prompt-for-expression-map)
1195 (progn
1196 (setq xscheme-prompt-for-expression-map
1197 (copy-keymap minibuffer-local-map))
1198 (substitute-key-definition 'exit-minibuffer
1199 'xscheme-prompt-for-expression-exit
1200 xscheme-prompt-for-expression-map)))
1201
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1202(defun xscheme-prompt-for-expression (prompt-string)
1203 (xscheme-send-string-2
1204 (read-from-minibuffer prompt-string nil xscheme-prompt-for-expression-map)))
1205
c5c3d778
DL
1206(defun xscheme-prompt-for-expression-exit ()
1207 (interactive)
1208 (if (eq (xscheme-region-expression-p (point-min) (point-max)) 'one)
1209 (exit-minibuffer)
1210 (error "input must be a single, complete expression")))
1211
1212(defun xscheme-region-expression-p (start end)
1213 (save-excursion
1214 (let ((old-syntax-table (syntax-table)))
1215 (unwind-protect
1216 (progn
1217 (set-syntax-table scheme-mode-syntax-table)
1218 (let ((state (parse-partial-sexp start end)))
1219 (and (zerop (car state)) ;depth = 0
1220 (nth 2 state) ;last-sexp exists, i.e. >= 1 sexps
1221 (let ((state (parse-partial-sexp start (nth 2 state))))
1222 (if (nth 2 state) 'many 'one)))))
1223 (set-syntax-table old-syntax-table)))))
1224
1225(provide 'xscheme)
1226
cbee283d 1227;; arch-tag: cfc14adc-2917-409e-ad16-432e8d0017de
c5c3d778 1228;;; xscheme.el ends here