1;;; complete.el --- partial completion mechanism plus other goodies
2
3;; Copyright (C) 1990, 1991, 1992, 1993, 1999, 2000, 2001, 2002, 2003,
4;;   2004, 2005, 2006, 2007 Free Software Foundation, Inc.
5
6;; Author: Dave Gillespie <daveg@synaptics.com>
7;; Keywords: abbrev convenience
8;; Special thanks to Hallvard Furuseth for his many ideas and contributions.
9
10;; This file is part of GNU Emacs.
11
12;; GNU Emacs is free software; you can redistribute it and/or modify
13;; it under the terms of the GNU General Public License as published by
14;; the Free Software Foundation; either version 2, or (at your option)
15;; any later version.
16
17;; GNU Emacs is distributed in the hope that it will be useful,
18;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20;; GNU General Public License for more details.
21
22;; You should have received a copy of the GNU General Public License
23;; along with GNU Emacs; see the file COPYING.  If not, write to the
24;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
25;; Boston, MA 02110-1301, USA.
26
27;;; Commentary:
28
29;; Extended completion for the Emacs minibuffer.
30;;
31;; The basic idea is that the command name or other completable text is
32;; divided into words and each word is completed separately, so that
33;; "M-x p-b" expands to "M-x print-buffer".  If the entry is ambiguous
34;; each word is completed as much as possible and then the cursor is
35;; left at the first position where typing another letter will resolve
36;; the ambiguity.
37;;
38;; Word separators for this purpose are hyphen, space, and period.
39;; These would most likely occur in command names, Info menu items,
40;; and file names, respectively.  But all word separators are treated
41;; alike at all times.
42;;
43;; This completion package replaces the old-style completer's key
44;; bindings for TAB, SPC, RET, and `?'.  The old completer is still
45;; available on the Meta versions of those keys.  If you set
46;; PC-meta-flag to nil, the old completion keys will be left alone
47;; and the partial completer will use the Meta versions of the keys.
48
49
50;; Usage:  M-x partial-completion-mode.  During completable minibuffer entry,
51;;
52;;     TAB    means to do a partial completion;
53;;     SPC    means to do a partial complete-word;
54;;     RET    means to do a partial complete-and-exit;
55;;     ?      means to do a partial completion-help.
56;;
57;; If you set PC-meta-flag to nil, then TAB, SPC, RET, and ? perform
58;; original Emacs completions, and M-TAB etc. do partial completion.
59;; To do this, put the command,
60;;
61;;       (setq PC-meta-flag nil)
62;;
63;; in your .emacs file.  To load partial completion automatically, put
64;;
65;;       (partial-completion-mode t)
66;;
67;; in your .emacs file, too.  Things will be faster if you byte-compile
68;; this file when you install it.
69;;
70;; As an extra feature, in cases where RET would not normally
71;; complete (such as `C-x b'), the M-RET key will always do a partial
72;; complete-and-exit.  Thus `C-x b f.c RET' will select or create a
73;; buffer called "f.c", but `C-x b f.c M-RET' will select the existing
74;; buffer whose name matches that pattern (perhaps "filing.c").
75;; (PC-meta-flag does not affect this behavior; M-RET used to be
76;; undefined in this situation.)
77;;
78;; The regular M-TAB (lisp-complete-symbol) command also supports
79;; partial completion in this package.
80
81;; In addition, this package includes a feature for accessing include
82;; files.  For example, `C-x C-f <sys/time.h> RET' reads the file
83;; /usr/include/sys/time.h.  The variable PC-include-file-path is a
84;; list of directories in which to search for include files.  Completion
85;; is supported in include file names.
86
87
88;;; Code:
89
90(defgroup partial-completion nil
91  "Partial Completion of items."
92  :prefix "pc-"
93  :group 'minibuffer
94  :group 'convenience)
95
96(defcustom PC-first-char 'find-file
97  "Control how the first character of a string is to be interpreted.
98If nil, the first character of a string is not taken literally if it is a word
99delimiter, so that \".e\" matches \"*.e*\".
100If t, the first character of a string is always taken literally even if it is a
101word delimiter, so that \".e\" matches \".e*\".
102If non-nil and non-t, the first character is taken literally only for file name
103completion."
104  :type '(choice (const :tag "delimiter" nil)
105		 (const :tag "literal" t)
106		 (other :tag "find-file" find-file))
107  :group 'partial-completion)
108
109(defcustom PC-meta-flag t
110  "If non-nil, TAB means PC completion and M-TAB means normal completion.
111Otherwise, TAB means normal completion and M-TAB means Partial Completion."
112  :type 'boolean
113  :group 'partial-completion)
114
115(defcustom PC-word-delimiters "-_. "
116  "A string of characters treated as word delimiters for completion.
117Some arcane rules:
118If `]' is in this string, it must come first.
119If `^' is in this string, it must not come first.
120If `-' is in this string, it must come first or right after `]'.
121In other words, if S is this string, then `[S]' must be a valid Emacs regular
122expression (not containing character ranges like `a-z')."
123  :type 'string
124  :group 'partial-completion)
125
126(defcustom PC-include-file-path '("/usr/include" "/usr/local/include")
127  "A list of directories in which to look for include files.
128If nil, means use the colon-separated path in the variable $INCPATH instead."
129  :type '(repeat directory)
130  :group 'partial-completion)
131
132(defcustom PC-disable-includes nil
133  "If non-nil, include-file support in \\[find-file] is disabled."
134  :type 'boolean
135  :group 'partial-completion)
136
137(defvar PC-default-bindings t
138  "If non-nil, default partial completion key bindings are suppressed.")
139
140(defvar PC-env-vars-alist nil
141  "A list of the environment variable names and values.")
142
143
144(defun PC-bindings (bind)
145  (let ((completion-map minibuffer-local-completion-map)
146	(must-match-map minibuffer-local-must-match-map))
147    (cond ((not bind)
148	   ;; These bindings are the default bindings.  It would be better to
149	   ;; restore the previous bindings.
150	   (define-key read-expression-map "\e\t" 'lisp-complete-symbol)
151
152	   (define-key completion-map "\t"	'minibuffer-complete)
153	   (define-key completion-map " "	'minibuffer-complete-word)
154	   (define-key completion-map "?"	'minibuffer-completion-help)
155
156	   (define-key must-match-map "\t"	'minibuffer-complete)
157	   (define-key must-match-map " "	'minibuffer-complete-word)
158	   (define-key must-match-map "\r"	'minibuffer-complete-and-exit)
159	   (define-key must-match-map "\n"	'minibuffer-complete-and-exit)
160	   (define-key must-match-map "?"	'minibuffer-completion-help)
161
162	   (define-key global-map [remap lisp-complete-symbol]	nil))
163	  (PC-default-bindings
164	   (define-key read-expression-map "\e\t" 'PC-lisp-complete-symbol)
165
166	   (define-key completion-map "\t"	'PC-complete)
167	   (define-key completion-map " "	'PC-complete-word)
168	   (define-key completion-map "?"	'PC-completion-help)
169
170	   (define-key completion-map "\e\t"	'PC-complete)
171	   (define-key completion-map "\e "	'PC-complete-word)
172	   (define-key completion-map "\e\r"	'PC-force-complete-and-exit)
173	   (define-key completion-map "\e\n"	'PC-force-complete-and-exit)
174	   (define-key completion-map "\e?"	'PC-completion-help)
175
176	   (define-key must-match-map "\t"	'PC-complete)
177	   (define-key must-match-map " "	'PC-complete-word)
178	   (define-key must-match-map "\r"	'PC-complete-and-exit)
179	   (define-key must-match-map "\n"	'PC-complete-and-exit)
180	   (define-key must-match-map "?"	'PC-completion-help)
181
182	   (define-key must-match-map "\e\t"	'PC-complete)
183	   (define-key must-match-map "\e "	'PC-complete-word)
184	   (define-key must-match-map "\e\r"	'PC-complete-and-exit)
185	   (define-key must-match-map "\e\n"	'PC-complete-and-exit)
186	   (define-key must-match-map "\e?"	'PC-completion-help)
187
188	   (define-key global-map [remap lisp-complete-symbol]	'PC-lisp-complete-symbol)))))
189
190(defvar PC-do-completion-end nil
191  "Internal variable used by `PC-do-completion'.")
192
193(make-variable-buffer-local 'PC-do-completion-end)
194
195(defvar PC-goto-end nil
196   "Internal variable set in `PC-do-completion', used in
197`choose-completion-string-functions'.")
198
199(make-variable-buffer-local 'PC-goto-end)
200
201;;;###autoload
202(define-minor-mode partial-completion-mode
203  "Toggle Partial Completion mode.
204With prefix ARG, turn Partial Completion mode on if ARG is positive.
205
206When Partial Completion mode is enabled, TAB (or M-TAB if `PC-meta-flag' is
207nil) is enhanced so that if some string is divided into words and each word is
208delimited by a character in `PC-word-delimiters', partial words are completed
209as much as possible and `*' characters are treated likewise in file names.
210
211For example, M-x p-c-m expands to M-x partial-completion-mode since no other
212command begins with that sequence of characters, and
213\\[find-file] f_b.c TAB might complete to foo_bar.c if that file existed and no
214other file in that directory begins with that sequence of characters.
215
216Unless `PC-disable-includes' is non-nil, the `<...>' sequence is interpreted
217specially in \\[find-file].  For example,
218\\[find-file] <sys/time.h> RET finds the file `/usr/include/sys/time.h'.
219See also the variable `PC-include-file-path'.
220
221Partial Completion mode extends the meaning of `completion-auto-help' (which
222see), so that if it is neither nil nor t, Emacs shows the `*Completions*'
223buffer only on the second attempt to complete.  That is, if TAB finds nothing
224to complete, the first TAB just says \"Next char not unique\" and the
225second TAB brings up the `*Completions*' buffer."
226  :global t :group 'partial-completion
227  ;; Deal with key bindings...
228  (PC-bindings partial-completion-mode)
229  ;; Deal with include file feature...
230  (cond ((not partial-completion-mode)
231	 (remove-hook 'find-file-not-found-functions 'PC-look-for-include-file))
232	((not PC-disable-includes)
233	 (add-hook 'find-file-not-found-functions 'PC-look-for-include-file)))
234  ;; ... with some underhand redefining.
235  (cond ((not partial-completion-mode)
236         (ad-disable-advice 'read-file-name-internal 'around 'PC-include-file)
237         (ad-activate 'read-file-name-internal))
238	((not PC-disable-includes)
239         (ad-enable-advice 'read-file-name-internal 'around 'PC-include-file)
240         (ad-activate 'read-file-name-internal)))
241  ;; Adjust the completion selection in *Completion* buffers to the way
242  ;; we work.  The default minibuffer completion code only completes the
243  ;; text before point and leaves the text after point alone (new in
244  ;; Emacs-22).  In contrast we use the whole text and we even sometimes
245  ;; move point to a place before EOB, to indicate the first position where
246  ;; there's a difference, so when the user uses choose-completion, we have
247  ;; to trick choose-completion into replacing the whole minibuffer text
248  ;; rather than only the text before point.  --Stef
249  (funcall
250   (if partial-completion-mode 'add-hook 'remove-hook)
251   'choose-completion-string-functions
252   (lambda (choice buffer mini-p base-size)
253     ;; When completing M-: (lisp- ) with point before the ), it is
254     ;; not appropriate to go to point-max (unlike the filename case).
255     (if (and (not PC-goto-end)
256              mini-p)
257         (goto-char (point-max))
258       ;; Need a similar hack for the non-minibuffer-case -- gm.
259       (when PC-do-completion-end
260         (goto-char PC-do-completion-end)
261         (setq PC-do-completion-end nil)))
262     (setq PC-goto-end nil)
263     nil))
264  ;; Build the env-completion and mapping table.
265  (when (and partial-completion-mode (null PC-env-vars-alist))
266    (setq PC-env-vars-alist
267          (mapcar (lambda (string)
268                    (let ((d (string-match "=" string)))
269                      (cons (concat "$" (substring string 0 d))
270                            (and d (substring string (1+ d))))))
271                  process-environment))))
272
273
274(defun PC-complete ()
275  "Like minibuffer-complete, but allows \"b--di\"-style abbreviations.
276For example, \"M-x b--di\" would match `byte-recompile-directory', or any
277name which consists of three or more words, the first beginning with \"b\"
278and the third beginning with \"di\".
279
280The pattern \"b--d\" is ambiguous for `byte-recompile-directory' and
281`beginning-of-defun', so this would produce a list of completions
282just like when normal Emacs completions are ambiguous.
283
284Word-delimiters for the purposes of Partial Completion are \"-\", \"_\",
285\".\", and SPC."
286  (interactive)
287  (if (PC-was-meta-key)
288      (minibuffer-complete)
289    ;; If the previous command was not this one,
290    ;; never scroll, always retry completion.
291    (or (eq last-command this-command)
292	(setq minibuffer-scroll-window nil))
293    (let ((window minibuffer-scroll-window))
294      ;; If there's a fresh completion window with a live buffer,
295      ;; and this command is repeated, scroll that window.
296      (if (and window (window-buffer window)
297	       (buffer-name (window-buffer window)))
298	  (with-current-buffer (window-buffer window)
299	    (if (pos-visible-in-window-p (point-max) window)
300		(set-window-start window (point-min) nil)
301	      (scroll-other-window)))
302	(PC-do-completion nil)))))
303
304
305(defun PC-complete-word ()
306  "Like `minibuffer-complete-word', but allows \"b--di\"-style abbreviations.
307See `PC-complete' for details.
308This can be bound to other keys, like `-' and `.', if you wish."
309  (interactive)
310  (if (eq (PC-was-meta-key) PC-meta-flag)
311      (if (eq last-command-char ? )
312	  (minibuffer-complete-word)
313	(self-insert-command 1))
314    (self-insert-command 1)
315    (if (eobp)
316	(PC-do-completion 'word))))
317
318
319(defun PC-complete-space ()
320  "Like `minibuffer-complete-word', but allows \"b--di\"-style abbreviations.
321See `PC-complete' for details.
322This is suitable for binding to other keys which should act just like SPC."
323  (interactive)
324  (if (eq (PC-was-meta-key) PC-meta-flag)
325      (minibuffer-complete-word)
326    (insert " ")
327    (if (eobp)
328	(PC-do-completion 'word))))
329
330
331(defun PC-complete-and-exit ()
332  "Like `minibuffer-complete-and-exit', but allows \"b--di\"-style abbreviations.
333See `PC-complete' for details."
334  (interactive)
335  (if (eq (PC-was-meta-key) PC-meta-flag)
336      (minibuffer-complete-and-exit)
337    (PC-do-complete-and-exit)))
338
339(defun PC-force-complete-and-exit ()
340  "Like `minibuffer-complete-and-exit', but allows \"b--di\"-style abbreviations.
341See `PC-complete' for details."
342  (interactive)
343  (let ((minibuffer-completion-confirm nil))
344    (PC-do-complete-and-exit)))
345
346(defun PC-do-complete-and-exit ()
347  (if (= (point-max) (minibuffer-prompt-end))  ; Duplicate the "bug" that Info-menu relies on...
348      (exit-minibuffer)
349    (let ((flag (PC-do-completion 'exit)))
350      (and flag
351	   (if (or (eq flag 'complete)
352		   (not minibuffer-completion-confirm))
353	       (exit-minibuffer)
354	     (PC-temp-minibuffer-message " [Confirm]"))))))
355
356
357(defun PC-completion-help ()
358  "Like `minibuffer-completion-help', but allows \"b--di\"-style abbreviations.
359See `PC-complete' for details."
360  (interactive)
361  (if (eq (PC-was-meta-key) PC-meta-flag)
362      (minibuffer-completion-help)
363    (PC-do-completion 'help)))
364
365(defun PC-was-meta-key ()
366  (or (/= (length (this-command-keys)) 1)
367      (let ((key (aref (this-command-keys) 0)))
368	(if (integerp key)
369	    (>= key 128)
370	  (not (null (memq 'meta (event-modifiers key))))))))
371
372
373(defvar PC-ignored-extensions 'empty-cache)
374(defvar PC-delims 'empty-cache)
375(defvar PC-ignored-regexp nil)
376(defvar PC-word-failed-flag nil)
377(defvar PC-delim-regex nil)
378(defvar PC-ndelims-regex nil)
379(defvar PC-delims-list nil)
380
381(defvar PC-completion-as-file-name-predicate
382  (lambda () minibuffer-completing-file-name)
383  "A function testing whether a minibuffer completion now will work filename-style.
384The function takes no arguments, and typically looks at the value
385of `minibuffer-completion-table' and the minibuffer contents.")
386
387;; Returns the sequence of non-delimiter characters that follow regexp in string.
388(defun PC-chunk-after (string regexp)
389  (if (not (string-match regexp string))
390      (let ((message (format "String %s didn't match regexp %s" string regexp)))
391	(message message)
392	(error message)))
393  (let ((result (substring string (match-end 0))))
394    ;; result may contain multiple chunks
395    (if (string-match PC-delim-regex result)
396	(setq result (substring result 0 (match-beginning 0))))
397    result))
398
399(defun test-completion-ignore-case (str table pred)
400  "Like `test-completion', but ignores case when possible."
401  ;; Binding completion-ignore-case to nil ensures, for compatibility with
402  ;; standard completion, that the return value is exactly one of the
403  ;; possibilities.  Do this binding only if pred is nil, out of paranoia;
404  ;; perhaps it is safe even if pred is non-nil.
405  (if pred
406      (test-completion str table pred)
407    (let ((completion-ignore-case nil))
408      (test-completion str table pred))))
409
410;; The following function is an attempt to work around two problems:
411
412;; (1) When complete.el was written, (try-completion "" '(("") (""))) used to
413;; return the value "".  With a change from 2002-07-07 it returns t which caused
414;; `PC-lisp-complete-symbol' to fail with a "Wrong type argument: sequencep, t"
415;; error.  `PC-try-completion' returns STRING in this case.
416
417;; (2) (try-completion "" '((""))) returned t before the above-mentioned change.
418;; Since `PC-chop-word' operates on the return value of `try-completion' this
419;; case might have provoked a similar error as in (1).  `PC-try-completion'
420;; returns "" instead.  I don't know whether this is a real problem though.
421
422;; Since `PC-try-completion' is not a guaranteed to fix these bugs reliably, you
423;; should try to look at the following discussions when you encounter problems:
424;; - emacs-pretest-bug ("Partial Completion" starting 2007-02-23),
425;; - emacs-devel ("[address-of-OP: Partial completion]" starting 2007-02-24),
426;; - emacs-devel ("[address-of-OP: EVAL and mouse selection in *Completions*]"
427;;   starting 2007-03-05).
428(defun PC-try-completion (string alist &optional predicate)
429  "Like `try-completion' but return STRING instead of t."
430  (let ((result (try-completion string alist predicate)))
431    (if (eq result t) string result)))
432
433;; TODO document MODE magic...
434(defun PC-do-completion (&optional mode beg end goto-end)
435  "Internal function to do the work of partial completion.
436Text to be completed lies between BEG and END.  Normally when
437replacing text in the minibuffer, this function replaces up to
438point-max (as is appropriate for completing a file name).  If
439GOTO-END is non-nil, however, it instead replaces up to END."
440  (or beg (setq beg (minibuffer-prompt-end)))
441  (or end (setq end (point-max)))
442  (let* ((table minibuffer-completion-table)
443	 (pred minibuffer-completion-predicate)
444	 (filename (funcall PC-completion-as-file-name-predicate))
445	 (dirname nil) ; non-nil only if a filename is being completed
446	 ;; The following used to be "(dirlength 0)" which caused the erasure of
447	 ;; the entire buffer text before `point' when inserting a completion
448	 ;; into a buffer.
449	 dirlength
450	 (str (buffer-substring beg end))
451	 (incname (and filename (string-match "<\\([^\"<>]*\\)>?$" str)))
452	 (ambig nil)
453	 basestr origstr
454	 env-on
455	 regex
456	 p offset
457	 (poss nil)
458	 helpposs
459	 (case-fold-search completion-ignore-case))
460
461    ;; Check if buffer contents can already be considered complete
462    (if (and (eq mode 'exit)
463	     (test-completion str table pred))
464	(progn
465	  ;; If completion-ignore-case is non-nil, insert the
466	  ;; completion string since that may have a different case.
467	  (when completion-ignore-case
468	    (setq str (PC-try-completion str table pred))
469	    (delete-region beg end)
470	    (insert str))
471	  'complete)
472
473      ;; Do substitutions in directory names
474      (and filename
475           (setq basestr (or (file-name-directory str) ""))
476           (setq dirlength (length basestr))
477	   ;; Do substitutions in directory names
478           (setq p (substitute-in-file-name basestr))
479           (not (string-equal basestr p))
480           (setq str (concat p (file-name-nondirectory str)))
481           (progn
482	     (delete-region beg end)
483	     (insert str)
484	     (setq end (+ beg (length str)))))
485
486      ;; Prepare various delimiter strings
487      (or (equal PC-word-delimiters PC-delims)
488	  (setq PC-delims PC-word-delimiters
489		PC-delim-regex (concat "[" PC-delims "]")
490		PC-ndelims-regex (concat "[^" PC-delims "]*")
491		PC-delims-list (append PC-delims nil)))
492
493      ;; Add wildcards if necessary
494      (and filename
495           (let ((dir (file-name-directory str))
496                 (file (file-name-nondirectory str))
497		 ;; The base dir for file-completion is passed in `predicate'.
498		 (default-directory (expand-file-name pred)))
499             (while (and (stringp dir) (not (file-directory-p dir)))
500               (setq dir (directory-file-name dir))
501               (setq file (concat (replace-regexp-in-string
502                                   PC-delim-regex "*\\&"
503                                   (file-name-nondirectory dir))
504                                  "*/" file))
505               (setq dir (file-name-directory dir)))
506             (setq origstr str str (concat dir file))))
507
508      ;; Look for wildcard expansions in directory name
509      (and filename
510	   (string-match "\\*.*/" str)
511	   (let ((pat str)
512		 ;; The base dir for file-completion is passed in `predicate'.
513		 (default-directory (expand-file-name pred))
514		 files)
515	     (setq p (1+ (string-match "/[^/]*\\'" pat)))
516	     (while (setq p (string-match PC-delim-regex pat p))
517	       (setq pat (concat (substring pat 0 p)
518				 "*"
519				 (substring pat p))
520		     p (+ p 2)))
521	     (setq files (PC-expand-many-files (concat pat "*")))
522	     (if files
523		 (let ((dir (file-name-directory (car files)))
524		       (p files))
525		   (while (and (setq p (cdr p))
526			       (equal dir (file-name-directory (car p)))))
527		   (if p
528		       (setq filename nil table nil pred nil
529			     ambig t)
530		     (delete-region beg end)
531		     (setq str (concat dir (file-name-nondirectory str)))
532		     (insert str)
533		     (setq end (+ beg (length str)))))
534	       (if origstr
535                   ;; If the wildcards were introduced by us, it's possible
536                   ;; that read-file-name-internal (especially our
537                   ;; PC-include-file advice) can still find matches for the
538                   ;; original string even if we couldn't, so remove the
539                   ;; added wildcards.
540                   (setq str origstr)
541		 (setq filename nil table nil pred nil)))))
542
543      ;; Strip directory name if appropriate
544      (if filename
545	  (if incname
546	      (setq basestr (substring str incname)
547		    dirname (substring str 0 incname))
548	    (setq basestr (file-name-nondirectory str)
549		  dirname (file-name-directory str))
550	    ;; Make sure str is consistent with its directory and basename
551	    ;; parts.  This is important on DOZe'NT systems when str only
552	    ;; includes a drive letter, like in "d:".
553	    (setq str (concat dirname basestr)))
554	(setq basestr str))
555
556      ;; Convert search pattern to a standard regular expression
557      (setq regex (regexp-quote basestr)
558	    offset (if (and (> (length regex) 0)
559			    (not (eq (aref basestr 0) ?\*))
560			    (or (eq PC-first-char t)
561				(and PC-first-char filename))) 1 0)
562	    p offset)
563      (while (setq p (string-match PC-delim-regex regex p))
564	(if (eq (aref regex p) ? )
565	    (setq regex (concat (substring regex 0 p)
566				PC-ndelims-regex
567				PC-delim-regex
568				(substring regex (1+ p)))
569		  p (+ p (length PC-ndelims-regex) (length PC-delim-regex)))
570	  (let ((bump (if (memq (aref regex p)
571				'(?$ ?^ ?\. ?* ?+ ?? ?[ ?] ?\\))
572			  -1 0)))
573	    (setq regex (concat (substring regex 0 (+ p bump))
574				PC-ndelims-regex
575				(substring regex (+ p bump)))
576		  p (+ p (length PC-ndelims-regex) 1)))))
577      (setq p 0)
578      (if filename
579	  (while (setq p (string-match "\\\\\\*" regex p))
580	    (setq regex (concat (substring regex 0 p)
581				"[^/]*"
582				(substring regex (+ p 2))))))
583      ;;(setq the-regex regex)
584      (setq regex (concat "\\`" regex))
585
586      (and (> (length basestr) 0)
587           (= (aref basestr 0) ?$)
588           (setq env-on t
589                 table PC-env-vars-alist
590                 pred nil))
591
592      ;; Find an initial list of possible completions
593      (if (not (setq p (string-match (concat PC-delim-regex
594					     (if filename "\\|\\*" ""))
595				     str
596				     (+ (length dirname) offset))))
597
598	  ;; Minibuffer contains no hyphens -- simple case!
599	  (setq poss (all-completions (if env-on
600					  basestr str)
601				      table
602				      pred))
603
604	;; Use all-completions to do an initial cull.  This is a big win,
605	;; since all-completions is written in C!
606	(let ((compl (all-completions (if env-on
607					  (file-name-nondirectory (substring str 0 p))
608					(substring str 0 p))
609                                      table
610                                      pred)))
611	  (setq p compl)
612	  (while p
613	    (and (string-match regex (car p))
614		 (progn
615		   (set-text-properties 0 (length (car p)) '() (car p))
616		   (setq poss (cons (car p) poss))))
617	    (setq p (cdr p)))))
618
619      ;; If table had duplicates, they can be here.
620      (delete-dups poss)
621
622      ;; Handle completion-ignored-extensions
623      (and filename
624           (not (eq mode 'help))
625           (let ((p2 poss))
626
627             ;; Build a regular expression representing the extensions list
628             (or (equal completion-ignored-extensions PC-ignored-extensions)
629                 (setq PC-ignored-regexp
630                       (concat "\\("
631                               (mapconcat
632                                'regexp-quote
633                                (setq PC-ignored-extensions
634                                      completion-ignored-extensions)
635                                "\\|")
636                               "\\)\\'")))
637
638             ;; Check if there are any without an ignored extension.
639             ;; Also ignore `.' and `..'.
640             (setq p nil)
641             (while p2
642               (or (string-match PC-ignored-regexp (car p2))
643                   (string-match "\\(\\`\\|/\\)[.][.]?/?\\'" (car p2))
644                   (setq p (cons (car p2) p)))
645               (setq p2 (cdr p2)))
646
647             ;; If there are "good" names, use them
648             (and p (setq poss p))))
649
650      ;; Now we have a list of possible completions
651      (cond
652
653       ;; No valid completions found
654       ((null poss)
655	(if (and (eq mode 'word)
656		 (not PC-word-failed-flag))
657	    (let ((PC-word-failed-flag t))
658	      (delete-backward-char 1)
659	      (PC-do-completion 'word))
660	  (beep)
661	  (PC-temp-minibuffer-message (if ambig
662					  " [Ambiguous dir name]"
663					(if (eq mode 'help)
664					    " [No completions]"
665					  " [No match]")))
666	  nil))
667
668       ;; More than one valid completion found
669       ((or (cdr (setq helpposs poss))
670	    (memq mode '(help word)))
671
672	;; Is the actual string one of the possible completions?
673	(setq p (and (not (eq mode 'help)) poss))
674	(while (and p
675		    (not (string-equal (car p) basestr)))
676	  (setq p (cdr p)))
677	(and p (null mode)
678	     (PC-temp-minibuffer-message " [Complete, but not unique]"))
679	(if (and p
680		 (not (and (null mode)
681			   (eq this-command last-command))))
682	    t
683
684	  ;; If ambiguous, try for a partial completion
685	  (let ((improved nil)
686		prefix
687		(pt nil)
688		(skip "\\`"))
689
690	    ;; Check if next few letters are the same in all cases
691	    (if (and (not (eq mode 'help))
692		     (setq prefix (PC-try-completion
693				   (PC-chunk-after basestr skip) poss)))
694		(let ((first t) i)
695		  ;; Retain capitalization of user input even if
696		  ;; completion-ignore-case is set.
697		  (if (eq mode 'word)
698		      (setq prefix (PC-chop-word prefix basestr)))
699		  (goto-char (+ beg (length dirname)))
700		  (while (and (progn
701				(setq i 0) ; index into prefix string
702				(while (< i (length prefix))
703				  (if (and (< (point) end)
704					   (eq (downcase (aref prefix i))
705					       (downcase (following-char))))
706				      ;; same char (modulo case); no action
707				      (forward-char 1)
708				    (if (and (< (point) end)
709					     (and (looking-at " ")
710                                                  (memq (aref prefix i)
711							PC-delims-list)))
712					;; replace " " by the actual delimiter
713					(progn
714					  (delete-char 1)
715					  (insert (substring prefix i (1+ i))))
716				      ;; insert a new character
717				      (progn
718                                        (and filename (looking-at "\\*")
719                                             (progn
720                                               (delete-char 1)
721                                               (setq end (1- end))))
722					(setq improved t)
723                                        (insert (substring prefix i (1+ i)))
724					(setq end (1+ end)))))
725				  (setq i (1+ i)))
726				(or pt (setq pt (point)))
727				(looking-at PC-delim-regex))
728			      (setq skip (concat skip
729						 (regexp-quote prefix)
730						 PC-ndelims-regex)
731				    prefix (PC-try-completion
732					    (PC-chunk-after
733					     ;; not basestr, because that does
734					     ;; not reflect insertions
735					     (buffer-substring
736					      (+ beg (length dirname)) end)
737					     skip)
738					    (mapcar
739                                             (lambda (x)
740                                               (when (string-match skip x)
741                                                 (substring x (match-end 0))))
742					     poss)))
743			      (or (> i 0) (> (length prefix) 0))
744			      (or (not (eq mode 'word))
745				  (and first (> (length prefix) 0)
746				       (setq first nil
747					     prefix (substring prefix 0 1))))))
748		  (goto-char (if (eq mode 'word) end
749			       (or pt beg)))))
750
751	    (if (and (eq mode 'word)
752		     (not PC-word-failed-flag))
753
754		(if improved
755
756		    ;; We changed it... would it be complete without the space?
757		    (if (test-completion (buffer-substring 1 (1- end))
758                                         table pred)
759			(delete-region (1- end) end)))
760
761	      (if improved
762
763		  ;; We changed it... enough to be complete?
764		  (and (eq mode 'exit)
765		       (test-completion-ignore-case (field-string) table pred))
766
767		;; If totally ambiguous, display a list of completions
768		(if (or (eq completion-auto-help t)
769			(and completion-auto-help
770			     (eq last-command this-command))
771			(eq mode 'help))
772                    (let ((prompt-end (minibuffer-prompt-end)))
773                      (with-output-to-temp-buffer "*Completions*"
774                        (display-completion-list (sort helpposs 'string-lessp))
775                        (setq PC-do-completion-end end
776                              PC-goto-end goto-end)
777                        (with-current-buffer standard-output
778                          ;; Record which part of the buffer we are completing
779                          ;; so that choosing a completion from the list
780                          ;; knows how much old text to replace.
781                          ;; This was briefly nil in the non-dirname case.
782                          ;; However, if one calls PC-lisp-complete-symbol
783                          ;; on "(ne-f" with point on the hyphen, PC offers
784                          ;; all completions starting with "(ne", some of
785                          ;; which do not match the "-f" part (maybe it
786                          ;; should not, but it does). In such cases,
787                          ;; completion gets confused trying to figure out
788                          ;; how much to replace, so we tell it explicitly
789                          ;; (ie, the number of chars in the buffer before beg).
790                          ;;
791                          ;; Note that choose-completion-string-functions
792                          ;; plays around with point.
793                          (setq completion-base-size (if dirname
794                                                         dirlength
795                                                       (- beg prompt-end))))))
796		  (PC-temp-minibuffer-message " [Next char not unique]"))
797		nil)))))
798
799       ;; Only one possible completion
800       (t
801	(if (and (equal basestr (car poss))
802		 (not (and env-on filename)))
803	    (if (null mode)
804		(PC-temp-minibuffer-message " [Sole completion]"))
805	  (delete-region beg end)
806	  (insert (format "%s"
807			  (if filename
808			      (substitute-in-file-name (concat dirname (car poss)))
809			    (car poss)))))
810	t)))))
811
812(defun PC-chop-word (new old)
813  (let ((i -1)
814	(j -1))
815    (while (and (setq i (string-match PC-delim-regex old (1+ i)))
816		(setq j (string-match PC-delim-regex new (1+ j)))))
817    (if (and j
818	     (or (not PC-word-failed-flag)
819		 (setq j (string-match PC-delim-regex new (1+ j)))))
820	(substring new 0 (1+ j))
821      new)))
822
823(defvar PC-not-minibuffer nil)
824
825(defun PC-temp-minibuffer-message (message)
826  "A Lisp version of `temp_minibuffer_message' from minibuf.c."
827  (cond (PC-not-minibuffer
828	 (message message)
829	 (sit-for 2)
830	 (message ""))
831	((fboundp 'temp-minibuffer-message)
832	 (temp-minibuffer-message message))
833	(t
834	 (let ((point-max (point-max)))
835	   (save-excursion
836	     (goto-char point-max)
837	     (insert message))
838	   (let ((inhibit-quit t))
839	     (sit-for 2)
840	     (delete-region point-max (point-max))
841	     (when quit-flag
842	       (setq quit-flag nil
843		     unread-command-events '(7))))))))
844
845;; Does not need to be buffer-local (?) because only used when one
846;; PC-l-c-s immediately follows another.
847(defvar PC-lisp-complete-end nil
848  "Internal variable used by `PC-lisp-complete-symbol'.")
849
850(defun PC-lisp-complete-symbol ()
851  "Perform completion on Lisp symbol preceding point.
852That symbol is compared against the symbols that exist
853and any additional characters determined by what is there
854are inserted.
855If the symbol starts just after an open-parenthesis,
856only symbols with function definitions are considered.
857Otherwise, all symbols with function definitions, values
858or properties are considered."
859  (interactive)
860  (let* ((end (point))
861         ;; To complete the word under point, rather than just the portion
862         ;; before point, use this:
863;;;           (save-excursion
864;;;             (with-syntax-table lisp-mode-syntax-table
865;;;               (forward-sexp 1)
866;;;               (point))))
867	 (beg (save-excursion
868                (with-syntax-table lisp-mode-syntax-table
869                  (backward-sexp 1)
870                  (while (= (char-syntax (following-char)) ?\')
871                    (forward-char 1))
872                  (point))))
873	 (minibuffer-completion-table obarray)
874	 (minibuffer-completion-predicate
875	  (if (eq (char-after (1- beg)) ?\()
876	      'fboundp
877	    (function (lambda (sym)
878			(or (boundp sym) (fboundp sym)
879			    (symbol-plist sym))))))
880	 (PC-not-minibuffer t))
881    ;; http://lists.gnu.org/archive/html/emacs-devel/2007-03/msg01211.html
882    ;;
883    ;; This deals with cases like running PC-l-c-s on "M-: (n-f".
884    ;; The first call to PC-l-c-s expands this to "(ne-f", and moves
885    ;; point to the hyphen [1]. If one calls PC-l-c-s immediately after,
886    ;; then without the last-command check, one is offered all
887    ;; completions of "(ne", which is presumably not what one wants.
888    ;;
889    ;; This is arguably (at least, it seems to be the existing intended
890    ;; behaviour) what one _does_ want if point has been explicitly
891    ;; positioned on the hyphen. Note that if PC-do-completion (qv) binds
892    ;; completion-base-size to nil, then completion does not replace the
893    ;; correct amount of text in such cases.
894    ;;
895    ;; Neither of these problems occur when using PC for filenames in the
896    ;; minibuffer, because in that case PC-do-completion is called without
897    ;; an explicit value for END, and so uses (point-max). This is fine for
898    ;; a filename, because the end of the filename must be at the end of
899    ;; the minibuffer. The same is not true for lisp symbols.
900    ;;
901    ;; [1] An alternate fix would be to not move point to the hyphen
902    ;; in such cases, but that would make the behaviour different from
903    ;; that for filenames. It seems PC moves point to the site of the
904    ;; first difference between the possible completions.
905    ;;
906    ;; Alternatively alternatively, maybe end should be computed in
907    ;; the same way as beg. That would change the behaviour though.
908    (if (equal last-command 'PC-lisp-complete-symbol)
909        (PC-do-completion nil beg PC-lisp-complete-end t)
910      (if PC-lisp-complete-end
911          (move-marker PC-lisp-complete-end end)
912        (setq PC-lisp-complete-end (copy-marker end t)))
913      (PC-do-completion nil beg end t))))
914
915(defun PC-complete-as-file-name ()
916   "Perform completion on file names preceding point.
917 Environment vars are converted to their values."
918   (interactive)
919   (let* ((end (point))
920          (beg (if (re-search-backward "[^\\][ \t\n\"\`\'][^ \t\n\"\`\']"
921				       (point-min) t)
922                   (+ (point) 2)
923                   (point-min)))
924          (minibuffer-completion-table 'read-file-name-internal)
925          (minibuffer-completion-predicate "")
926          (PC-not-minibuffer t))
927     (goto-char end)
928     (PC-do-completion nil beg end)))
929
930;; Use the shell to do globbing.
931;; This could now use file-expand-wildcards instead.
932
933(defun PC-expand-many-files (name)
934  (with-current-buffer (generate-new-buffer " *Glob Output*")
935    (erase-buffer)
936    (when (and (file-name-absolute-p name)
937               (not (file-directory-p default-directory)))
938      ;; If the current working directory doesn't exist `shell-command'
939      ;; signals an error.  So if the file names we're looking for don't
940      ;; depend on the working directory, switch to a valid directory first.
941      (setq default-directory "/"))
942    (shell-command (concat "echo " name) t)
943    (goto-char (point-min))
944    ;; CSH-style shells were known to output "No match", whereas
945    ;; SH-style shells tend to simply output `name' when no match is found.
946    (if (looking-at (concat ".*No match\\|\\(^\\| \\)\\("
947			    (regexp-quote name)
948			    "\\|"
949			    (regexp-quote (expand-file-name name))
950			    "\\)\\( \\|$\\)"))
951	nil
952      (insert "(\"")
953      (while (search-forward " " nil t)
954	(delete-backward-char 1)
955	(insert "\" \""))
956      (goto-char (point-max))
957      (delete-backward-char 1)
958      (insert "\")")
959      (goto-char (point-min))
960      (let ((files (read (current-buffer))) (p nil))
961	(kill-buffer (current-buffer))
962	(or (equal completion-ignored-extensions PC-ignored-extensions)
963	    (setq PC-ignored-regexp
964		  (concat "\\("
965			  (mapconcat
966			   'regexp-quote
967			   (setq PC-ignored-extensions
968				 completion-ignored-extensions)
969			   "\\|")
970			  "\\)\\'")))
971	(setq p nil)
972	(while files
973          ;; This whole process of going through to shell, to echo, and
974          ;; finally parsing the output is a hack.  It breaks as soon as
975          ;; there are spaces in the file names or when the no-match
976          ;; message changes.  To make up for it, we check that what we read
977          ;; indeed exists, so we may miss some files, but we at least won't
978          ;; list non-existent ones.
979	  (or (not (file-exists-p (car files)))
980	      (string-match PC-ignored-regexp (car files))
981	      (setq p (cons (car files) p)))
982	  (setq files (cdr files)))
983	p))))
984
985;; Facilities for loading C header files.  This is independent from the
986;; main completion code.  See also the variable `PC-include-file-path'
987;; at top of this file.
988
989(defun PC-look-for-include-file ()
990  (if (string-match "[\"<]\\([^\"<>]*\\)[\">]?$" (buffer-file-name))
991      (let ((name (substring (buffer-file-name)
992			     (match-beginning 1) (match-end 1)))
993	    (punc (aref (buffer-file-name) (match-beginning 0)))
994	    (path nil)
995	    new-buf)
996	(kill-buffer (current-buffer))
997	(if (equal name "")
998	    (with-current-buffer (car (buffer-list))
999	      (save-excursion
1000		(beginning-of-line)
1001		(if (looking-at
1002		     "[ \t]*#[ \t]*include[ \t]+[<\"]\\(.+\\)[>\"][ \t]*[\n/]")
1003		    (setq name (buffer-substring (match-beginning 1)
1004						 (match-end 1))
1005			  punc (char-after (1- (match-beginning 1))))
1006		  ;; Suggested by Frank Siebenlist:
1007		  (if (or (looking-at
1008			   "[ \t]*([ \t]*load[ \t]+\"\\([^\"]+\\)\"")
1009			  (looking-at
1010			   "[ \t]*([ \t]*load-library[ \t]+\"\\([^\"]+\\)\"")
1011			  (looking-at
1012			   "[ \t]*([ \t]*require[ \t]+'\\([^\t )]+\\)[\t )]"))
1013		      (progn
1014			(setq name (buffer-substring (match-beginning 1)
1015						     (match-end 1))
1016			      punc ?\<
1017			      path load-path)
1018			(if (string-match "\\.elc$" name)
1019			    (setq name (substring name 0 -1))
1020			  (or (string-match "\\.el$" name)
1021			      (setq name (concat name ".el")))))
1022		    (error "Not on an #include line"))))))
1023	(or (string-match "\\.[[:alnum:]]+$" name)
1024	    (setq name (concat name ".h")))
1025	(if (eq punc ?\<)
1026	    (let ((path (or path (PC-include-file-path))))
1027	      (while (and path
1028			  (not (file-exists-p
1029				(concat (file-name-as-directory (car path))
1030					name))))
1031		(setq path (cdr path)))
1032	      (if path
1033		  (setq name (concat (file-name-as-directory (car path)) name))
1034		(error "No such include file: <%s>" name)))
1035	  (let ((dir (with-current-buffer (car (buffer-list))
1036		       default-directory)))
1037	    (if (file-exists-p (concat dir name))
1038		(setq name (concat dir name))
1039	      (error "No such include file: `%s'" name))))
1040	(setq new-buf (get-file-buffer name))
1041	(if new-buf
1042	    ;; no need to verify last-modified time for this!
1043	    (set-buffer new-buf)
1044	  (set-buffer (create-file-buffer name))
1045	  (erase-buffer)
1046	  (insert-file-contents name t))
1047	;; Returning non-nil with the new buffer current
1048	;; is sufficient to tell find-file to use it.
1049	t)
1050    nil))
1051
1052(defun PC-include-file-path ()
1053  (or PC-include-file-path
1054      (let ((env (getenv "INCPATH"))
1055	    (path nil)
1056	    pos)
1057	(or env (error "No include file path specified"))
1058	(while (setq pos (string-match ":[^:]+$" env))
1059	  (setq path (cons (substring env (1+ pos)) path)
1060		env (substring env 0 pos)))
1061	path)))
1062
1063;; This is adapted from lib-complete.el, by Mike Williams.
1064(defun PC-include-file-all-completions (file search-path &optional full)
1065  "Return all completions for FILE in any directory on SEARCH-PATH.
1066If optional third argument FULL is non-nil, returned pathnames should be
1067absolute rather than relative to some directory on the SEARCH-PATH."
1068  (setq search-path
1069	(mapcar (lambda (dir)
1070		  (if dir (file-name-as-directory dir) default-directory))
1071		search-path))
1072  (if (file-name-absolute-p file)
1073      ;; It's an absolute file name, so don't need search-path
1074      (progn
1075	(setq file (expand-file-name file))
1076	(file-name-all-completions
1077	 (file-name-nondirectory file) (file-name-directory file)))
1078    (let ((subdir (file-name-directory file))
1079	  (ndfile (file-name-nondirectory file))
1080	  file-lists)
1081      ;; Append subdirectory part to each element of search-path
1082      (if subdir
1083	  (setq search-path
1084		(mapcar (lambda (dir) (concat dir subdir))
1085			search-path)
1086		file ))
1087      ;; Make list of completions in each directory on search-path
1088      (while search-path
1089	(let* ((dir (car search-path))
1090	       (subdir (if full dir subdir)))
1091	  (if (file-directory-p dir)
1092	      (progn
1093		(setq file-lists
1094		      (cons
1095		       (mapcar (lambda (file) (concat subdir file))
1096			       (file-name-all-completions ndfile
1097							  (car search-path)))
1098		       file-lists))))
1099	  (setq search-path (cdr search-path))))
1100      ;; Compress out duplicates while building complete list (slloooow!)
1101      (let ((sorted (sort (apply 'nconc file-lists)
1102			  (lambda (x y) (not (string-lessp x y)))))
1103	    compressed)
1104	(while sorted
1105	  (if (equal (car sorted) (car compressed)) nil
1106	    (setq compressed (cons (car sorted) compressed)))
1107	  (setq sorted (cdr sorted)))
1108	compressed))))
1109
1110(defadvice read-file-name-internal (around PC-include-file disable)
1111  (if (string-match "<\\([^\"<>]*\\)>?\\'" (ad-get-arg 0))
1112      (let* ((string (ad-get-arg 0))
1113             (action (ad-get-arg 2))
1114             (name (match-string 1 string))
1115	     (str2 (substring string (match-beginning 0)))
1116	     (completion-table
1117	      (mapcar (lambda (x)
1118                        (format (if (string-match "/\\'" x) "<%s" "<%s>") x))
1119		      (PC-include-file-all-completions
1120		       name (PC-include-file-path)))))
1121        (setq ad-return-value
1122              (cond
1123               ((not completion-table) nil)
1124               ((eq action 'lambda) (test-completion str2 completion-table nil))
1125               ((eq action nil) (PC-try-completion str2 completion-table nil))
1126               ((eq action t) (all-completions str2 completion-table nil)))))
1127    ad-do-it))
1128
1129
1130(provide 'complete)
1131
1132;; arch-tag: fc7e2768-ff44-4e22-b579-4d825b968458
1133;;; complete.el ends here
1134