1 ;;; hide-ifdef-mode.el --- hides selected code within ifdef.
3 ;;; Copyright (C) 1988 Free Software Foundation, Inc.
5 ;; Author: Dan LaLiberte <liberte@a.cs.uiuc.edu>
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software; you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation; either version 2, or (at your option)
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to
22 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
26 ;;; To initialize, toggle the hide-ifdef minor mode with
28 ;;; M-x hide-ifdef-mode
30 ;;; This will set up key bindings and call hide-ifdef-mode-hook if it
31 ;;; has a value. To explicitly hide ifdefs using a buffer-local
32 ;;; define list (default empty), type
34 ;;; M-x hide-ifdefs or C-c h
36 ;;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't
37 ;;; pass through. The support of constant expressions in #if lines is
38 ;;; limited to identifiers, parens, and the operators: &&, ||, !, and
39 ;;; "defined". Please extend this.
41 ;;; The hidden code is marked by ellipses (...). Be
42 ;;; cautious when editing near ellipses, since the hidden text is
43 ;;; still in the buffer, and you can move the point into it and modify
44 ;;; text unawares. If you don't want to see the ellipses, set
45 ;;; selective-display-ellipses to nil. But this can be dangerous.
46 ;;; You can make your buffer read-only while hide-ifdef-hiding by setting
47 ;;; hide-ifdef-read-only to a non-nil value. You can toggle this
48 ;;; variable with hide-ifdef-toggle-read-only (C-c C-q).
50 ;;; You can undo the effect of hide-ifdefs by typing
52 ;;; M-x show-ifdefs or C-c s
54 ;;; Use M-x hide-ifdef-define (C-c d) to define a symbol.
55 ;;; Use M-x hide-ifdef-undef (C-c u) to undefine a symbol.
57 ;;; If you define or undefine a symbol while hide-ifdef-mode is in effect,
58 ;;; the display will be updated. Only the define list for the current
59 ;;; buffer will be affected. You can save changes to the local define
60 ;;; list with hide-ifdef-set-define-alist. This adds entries
61 ;;; to hide-ifdef-define-alist.
63 ;;; If you have defined a hide-ifdef-mode-hook, you can set
64 ;;; up a list of symbols that may be used by hide-ifdefs as in the
65 ;;; following example:
67 ;;; (setq hide-ifdef-mode-hook
69 ;;; (if (not hide-ifdef-define-alist)
70 ;;; (setq hide-ifdef-define-alist
74 ;;; (hide-ifdef-use-define-alist 'list2) ; use list2 by default
77 ;;; You can call hide-ifdef-use-define-alist (C-c u) at any time to specify
78 ;;; another list to use.
80 ;;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called,
81 ;;; set hide-ifdef-initially to non-nil.
83 ;;; If you set hide-ifdef-lines to t, hide-ifdefs hides all the #ifdef lines.
84 ;;; In the absence of highlighting, that might be a bad idea. If you set
85 ;;; hide-ifdef-lines to nil (the default), the surrounding preprocessor
86 ;;; lines will be displayed. That can be confusing in its own
87 ;;; right. Other variations on display are possible, but not much
90 ;;; You can explicitly hide or show individual ifdef blocks irrespective
91 ;;; of the define list by using hide-ifdef-block and show-ifdef-block.
93 ;;; You can move the point between ifdefs with forward-ifdef, backward-ifdef,
94 ;;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef.
96 ;;; If you have minor-mode-alist in your mode line (the default) two labels
97 ;;; may appear. "Ifdef" will appear when hide-ifdef-mode is active. "Hiding"
98 ;;; will appear when text may be hidden ("hide-ifdef-hiding" is non-nil).
100 ;;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL.
101 ;;; Extensively modified by Daniel LaLiberte (while at Gould).
103 ;;; You may freely modify and distribute this, but keep a record
104 ;;; of modifications and send comments to:
105 ;;; liberte@a.cs.uiuc.edu or ihnp4!uiucdcs!liberte
106 ;;; I will continue to upgrade hide-ifdef-mode
107 ;;; with your contributions.
111 ;;; Revision 1.7 88/02/16 03:12:58 liberte
112 ;;; Fixed comments and doc strings.
113 ;;; Added optional prefix arg for ifdef motion commands.
115 ;;; Revision 1.6 88/02/05 00:36:18 liberte
117 ;;; 1. A multi-line comment that starts on an #ifdef line
118 ;;; now ends on that line.
119 ;;; 2. Fix bad function name: hide-hif-ifdef-toggle-read-only
120 ;;; 3. Make ifdef-block hiding work outside of ifdefs.
122 ;;; Revision 1.5 88/01/31 23:19:31 liberte
124 ;;; Prefix internal names with "hif-".
126 ;;; Revision 1.4 88/01/30 14:09:38 liberte
127 ;;; Add hide-ifdef-hiding and hide-ifdef-mode to minor-mode-alist.
129 ;;; Revision 1.3 88/01/29 00:38:19 liberte
131 ;;; 1. Function "defined" is just like lookup.
132 ;;; 2. Skip to newline or cr in case text is hidden.
133 ;;; 3. Use car of token list if just one symbol.
135 ;;; Revision 1.2 88/01/28 23:32:46 liberte
136 ;;; Use hide-ifdef-mode-prefix-key.
137 ;;; Copy current-local-map so other buffers do not get
138 ;;; hide-ifdef-mode bindings.
143 (defvar hide-ifdef-mode-map nil
144 "Keymap used with Hide-Ifdef mode")
146 (defconst hide-ifdef-mode-prefix-key "\C-c"
147 "Prefix key for all Hide-Ifdef mode commands.")
149 (defvar hide-ifdef-mode-map-before nil
150 "Buffer-local variable to store a copy of the local keymap
151 before `hide-ifdef-mode' modifies it.")
153 (defun define-hide-ifdef-mode-map ()
154 (if hide-ifdef-mode-map
155 () ; dont redefine it.
156 (setq hide-ifdef-mode-map (make-sparse-keymap))
157 (define-key hide-ifdef-mode-map "\ed" 'hide-ifdef-define)
158 (define-key hide-ifdef-mode-map "\eu" 'hide-ifdef-undef)
159 (define-key hide-ifdef-mode-map "\eD" 'hide-ifdef-set-define-alist)
160 (define-key hide-ifdef-mode-map "\eU" 'hide-ifdef-use-define-alist)
162 (define-key hide-ifdef-mode-map "\eh" 'hide-ifdefs)
163 (define-key hide-ifdef-mode-map "\es" 'show-ifdefs)
164 (define-key hide-ifdef-mode-map "\C-h" 'hide-ifdef-block)
165 (define-key hide-ifdef-mode-map "\C-s" 'show-ifdef-block)
167 (define-key hide-ifdef-mode-map "\C-f" 'forward-ifdef)
168 (define-key hide-ifdef-mode-map "\C-b" 'backward-ifdef)
169 (define-key hide-ifdef-mode-map "\C-d" 'down-ifdef)
170 (define-key hide-ifdef-mode-map "\C-u" 'up-ifdef)
171 (define-key hide-ifdef-mode-map "\C-n" 'next-ifdef)
172 (define-key hide-ifdef-mode-map "\C-p" 'previous-ifdef)
173 (define-key hide-ifdef-mode-map "\C-q" 'hide-ifdef-toggle-read-only)
174 (let ((where (where-is-internal 'toggle-read-only nil nil t)))
176 (define-key hide-ifdef-mode-map
178 'hide-ifdef-toggle-outside-read-only)))
180 (fset 'hide-ifdef-mode-map hide-ifdef-mode-map) ; the function is the map
183 (defun hif-update-mode-line ()
184 "Update mode-line by setting buffer-modified to itself."
185 (set-buffer-modified-p (buffer-modified-p)))
187 (defvar hide-ifdef-mode nil
188 "non-nil when hide-ifdef-mode is activated.")
190 (defvar hide-ifdef-hiding nil
191 "non-nil when text may be hidden.")
193 (or (assq 'hide-ifdef-hiding minor-mode-alist)
194 (setq minor-mode-alist
195 (cons '(hide-ifdef-hiding " Hiding")
198 (or (assq 'hide-ifdef-mode minor-mode-alist)
199 (setq minor-mode-alist
200 (cons '(hide-ifdef-mode " Ifdef")
204 (defun hide-ifdef-mode (arg)
205 "Toggle Hide-Ifdef mode. This is a minor mode, albeit a large one.
206 With ARG, turn Hide-Ifdef mode on iff arg is positive.
207 In Hide-Ifdef mode, code within #ifdef constructs that the C preprocessor
208 would eliminate may be hidden from view. Several variables affect
209 how the hiding is done:
212 An association list of defined and undefined symbols for the
213 current buffer. Initially, the global value of `hide-ifdef-env'
216 hide-ifdef-define-alist
217 An association list of defined symbol lists.
218 Use `hide-ifdef-set-define-alist' to save the current `hide-ifdef-env'
219 and `hide-ifdef-use-define-alist' to set the current `hide-ifdef-env'
220 from one of the lists in `hide-ifdef-define-alist'.
223 Set to non-nil to not show #if, #ifdef, #ifndef, #else, and
224 #endif lines when hiding.
227 Indicates whether `hide-ifdefs' should be called when Hide-Ifdef mode
231 Set to non-nil if you want to make buffers read only while hiding.
232 After `show-ifdefs', read-only status is restored to previous value.
234 \\{hide-ifdef-mode-map}"
237 (make-local-variable 'hide-ifdef-mode)
238 (setq hide-ifdef-mode
240 (not hide-ifdef-mode)
241 (> (prefix-numeric-value arg) 0)))
243 (hif-update-mode-line)
247 ; fix c-mode syntax table so we can recognize whole symbols.
248 (modify-syntax-entry ?_ "w")
249 (modify-syntax-entry ?& ".")
250 (modify-syntax-entry ?\| ".")
252 ; inherit global values
253 (make-local-variable 'hide-ifdef-env)
254 (setq hide-ifdef-env (default-value 'hide-ifdef-env))
256 (make-local-variable 'hide-ifdef-hiding)
257 (setq hide-ifdef-hiding (default-value 'hide-ifdef-hiding))
259 (make-local-variable 'hif-outside-read-only)
260 (setq hif-outside-read-only buffer-read-only)
262 (make-local-variable 'hide-ifdef-mode-map-before)
263 (setq hide-ifdef-mode-map-before (current-local-map))
264 (use-local-map (copy-keymap (current-local-map)))
265 (local-unset-key hide-ifdef-mode-prefix-key)
266 (local-set-key hide-ifdef-mode-prefix-key 'hide-ifdef-mode-map)
267 (define-hide-ifdef-mode-map)
269 (run-hooks 'hide-ifdef-mode-hook)
271 (if hide-ifdef-initially
274 (message "Enter hide-ifdef-mode.")
276 ; else end hide-ifdef-mode
277 (if hide-ifdef-hiding
279 (use-local-map hide-ifdef-mode-map-before)
280 (message "Exit hide-ifdef-mode.")
284 ;; from outline.el with docstring fixed.
285 (defun hif-outline-flag-region (from to flag)
286 "Hides or shows lines from FROM to TO, according to FLAG. If FLAG
287 is \\n (newline character) then text is shown, while if FLAG is \\^M
288 \(control-M) the text is hidden."
289 (let ((modp (buffer-modified-p)))
290 (unwind-protect (progn
291 (subst-char-in-region from to
292 (if (= flag ?\n) ?\^M ?\n)
294 (set-buffer-modified-p modp))
297 (defun hif-show-all ()
298 "Show all of the text in the current buffer."
300 (hif-outline-flag-region (point-min) (point-max) ?\n))
302 (defun hide-ifdef-region (start end)
303 "START is the start of a #if or #else form. END is the ending part.
304 Everything including these lines is made invisible."
305 (hif-outline-flag-region start end ?\^M)
308 (defun hif-show-ifdef-region (start end)
309 "Everything between START and END is made visible."
310 (hif-outline-flag-region start end ?\n)
315 ;===%%SF%% evaluation (Start) ===
317 (defvar hide-ifdef-evaluator 'eval
318 "The evaluator is given a canonical form and returns T if text under
319 that form should be displayed.")
321 (defvar hif-undefined-symbol nil
322 "...is by default considered to be false.")
324 (defvar hide-ifdef-env nil
325 "An alist of defined symbols and their values.")
328 (defun hif-set-var (var value)
329 "Prepend (var value) pair to hide-ifdef-env."
330 (setq hide-ifdef-env (cons (cons var value) hide-ifdef-env)))
333 (defun hif-lookup (var)
334 ; (message "hif-lookup %s" var)
335 (let ((val (assoc var hide-ifdef-env)))
338 hif-undefined-symbol)))
340 (defun hif-defined (var)
342 ; when #if expressions are fully supported, defined result should be 1
343 ; (if (assoc var hide-ifdef-env)
349 ;===%%SF%% evaluation (End) ===
353 ;===%%SF%% parsing (Start) ===
354 ;;; The code that understands what ifs and ifdef in files look like.
356 (defconst hif-cpp-prefix "\\(^\\|\r\\)[ \t]*#[ \t]*")
357 (defconst hif-ifndef-regexp (concat hif-cpp-prefix "ifndef"))
358 (defconst hif-ifx-regexp (concat hif-cpp-prefix "if\\(n?def\\)?[ \t]+"))
359 (defconst hif-else-regexp (concat hif-cpp-prefix "else"))
360 (defconst hif-endif-regexp (concat hif-cpp-prefix "endif"))
361 (defconst hif-ifx-else-endif-regexp
362 (concat hif-ifx-regexp "\\|" hif-else-regexp "\\|" hif-endif-regexp))
365 (defun hif-infix-to-prefix (token-list)
366 "Convert list of tokens in infix into prefix list"
367 ; (message "hif-infix-to-prefix: %s" token-list)
368 (if (= 1 (length token-list))
369 (` (hif-lookup (quote (, (car token-list)))))
370 (hif-parse-if-exp token-list))
373 ; pattern to match initial identifier, !, &&, ||, (, or ).
374 (defconst hif-token-regexp "^\\(!\\|&&\\|||\\|[()]\\|\\w+\\)")
375 (defconst hif-end-of-comment "\\*/")
378 (defun hif-tokenize (expr-string)
379 "Separate string into a list of tokens"
380 (let ((token-list nil)
382 (expr-length (length expr-string)))
384 (while (< expr-start expr-length)
385 ; (message "expr-start = %d" expr-start) (sit-for 1)
387 ((string-match "^[ \t]+" expr-string expr-start)
389 (setq expr-start (match-end 0))
390 ; stick newline in string so ^ matches on the next string-match
391 (aset expr-string (1- expr-start) ?\n)
394 ((string-match "^/\\*" expr-string expr-start)
395 (setq expr-start (match-end 0))
396 (aset expr-string (1- expr-start) ?\n)
398 (string-match hif-end-of-comment
399 expr-string expr-start) ; eat comment
400 (string-match "$" expr-string expr-start)) ; multi-line comment
401 (setq expr-start (match-end 0))
402 (aset expr-string (1- expr-start) ?\n)
405 ((string-match hif-token-regexp expr-string expr-start)
406 (let ((token (substring expr-string expr-start (match-end 0))))
407 (setq expr-start (match-end 0))
408 (aset expr-string (1- expr-start) ?\n)
409 ; (message "token: %s" token) (sit-for 1)
413 ((string-equal token "||") 'or)
414 ((string-equal token "&&") 'and)
415 ((string-equal token "!") 'not)
416 ((string-equal token "defined") 'hif-defined)
417 ((string-equal token "(") 'lparen)
418 ((string-equal token ")") 'rparen)
422 (t (error "Bad #if expression: %s" expr-string))
424 (nreverse token-list)
427 ;;;-----------------------------------------------------------------
428 ;;; Translate C preprocessor #if expressions using recursive descent.
429 ;;; This parser is limited to the operators &&, ||, !, and "defined".
431 (defun hif-parse-if-exp (token-list)
432 "Parse the TOKEN-LIST. Return translated list in prefix form."
436 (if token ; is there still a token?
437 (error "Error: unexpected token: %s" token))))
439 (defun hif-nexttoken ()
440 "Pop the next token from token-list into the let variable \"token\"."
441 (setq token (car token-list))
442 (setq token-list (cdr token-list))
446 "Parse and expression of the form
447 expr : term | expr '||' term."
448 (let ((result (hif-term)))
449 (while (eq token 'or)
451 (setq result (list 'or result (hif-term))))
455 "Parse a term of the form
456 term : factor | term '&&' factor."
457 (let ((result (hif-factor)))
458 (while (eq token 'and)
460 (setq result (list 'and result (hif-factor))))
464 "Parse a factor of the form
465 factor : '!' factor | '(' expr ')' | 'defined(' id ')' | id."
469 (list 'not (hif-factor)))
473 (let ((result (hif-expr)))
474 (if (not (eq token 'rparen))
475 (error "Bad token in parenthesized expression: %s" token)
479 ((eq token 'hif-defined)
481 (if (not (eq token 'lparen))
482 (error "Error: expected \"(\" after \"defined\""))
485 (if (memq token '(or and not hif-defined lparen rparen))
486 (error "Error: unexpected token: %s" token))
488 (if (not (eq token 'rparen))
489 (error "Error: expected \")\" after identifier"))
491 (` (hif-defined (quote (, ident))))
496 (if (memq ident '(or and))
497 (error "Error: missing identifier"))
499 (` (hif-lookup (quote (, ident))))
503 ;;;----------- end of parser -----------------------
506 (defun hif-canonicalize ()
507 "When at beginning of #ifX, returns a canonical (evaluatable)
508 form for the expression."
510 (let ((negate (looking-at hif-ifndef-regexp)))
511 (re-search-forward hif-ifx-regexp)
513 (buffer-substring (point)
514 (progn (skip-chars-forward "^\n\r") (point))))
515 (expr (hif-infix-to-prefix (hif-tokenize expr-string))))
516 ; (message "hif-canonicalized: %s" expr)
522 (defun hif-find-any-ifX ()
523 "Position at beginning of next #if, #ifdef, or #ifndef, including one on
525 ; (message "find ifX at %d" (point))
527 (re-search-forward hif-ifx-regexp (point-max) t)
528 (beginning-of-line)))
531 (defun hif-find-next-relevant ()
532 "Position at beginning of next #ifdef, #ifndef, #else, #endif,
533 NOT including one on this line."
534 ; (message "hif-find-next-relevant at %d" (point))
536 ; avoid infinite recursion by only going to beginning of line if match found
537 (if (re-search-forward hif-ifx-else-endif-regexp (point-max) t)
538 (beginning-of-line)))
540 (defun hif-find-previous-relevant ()
541 "Position at beginning of previous #ifdef, #ifndef, #else, #endif,
542 NOT including one on this line."
543 ; (message "hif-find-previous-relevant at %d" (point))
545 ; avoid infinite recursion by only going to beginning of line if match found
546 (if (re-search-backward hif-ifx-else-endif-regexp (point-min) t)
547 (beginning-of-line)))
550 (defun hif-looking-at-ifX () ;; Should eventually see #if
551 (looking-at hif-ifx-regexp))
552 (defun hif-looking-at-endif ()
553 (looking-at hif-endif-regexp))
554 (defun hif-looking-at-else ()
555 (looking-at hif-else-regexp))
559 (defun hif-ifdef-to-endif ()
560 "If positioned at #ifX or #else form, skip to corresponding #endif."
561 ; (message "hif-ifdef-to-endif at %d" (point)) (sit-for 1)
562 (hif-find-next-relevant)
563 (cond ((hif-looking-at-ifX)
564 (hif-ifdef-to-endif) ; find endif of nested if
565 (hif-ifdef-to-endif)) ; find outer endif or else
566 ((hif-looking-at-else)
567 (hif-ifdef-to-endif)) ; find endif following else
568 ((hif-looking-at-endif)
571 (error "Mismatched #ifdef #endif pair"))))
574 (defun hif-endif-to-ifdef ()
575 "If positioned at #endif form, skip backward to corresponding #ifX."
576 ; (message "hif-endif-to-ifdef at %d" (point))
577 (let ((start (point)))
578 (hif-find-previous-relevant)
579 (if (= start (point))
580 (error "Mismatched #ifdef #endif pair")))
581 (cond ((hif-looking-at-endif)
582 (hif-endif-to-ifdef) ; find beginning of nested if
583 (hif-endif-to-ifdef)) ; find beginning of outer if or else
584 ((hif-looking-at-else)
585 (hif-endif-to-ifdef))
586 ((hif-looking-at-ifX)
588 (t))) ; never gets here
591 (defun forward-ifdef (&optional arg)
592 "Move point to beginning of line of the next ifdef-endif.
593 With argument, do this that many times."
595 (or arg (setq arg 1))
597 (backward-ifdef (- arg)))
600 (let ((start (point)))
601 (if (not (hif-looking-at-ifX))
602 (hif-find-next-relevant))
603 (if (hif-looking-at-ifX)
606 (error "No following #ifdef")
610 (defun backward-ifdef (&optional arg)
611 "Move point to beginning of the previous ifdef-endif.
612 With argument, do this that many times."
614 (or arg (setq arg 1))
616 (forward-ifdef (- arg)))
620 (let ((start (point)))
621 (if (not (hif-looking-at-endif))
622 (hif-find-previous-relevant))
623 (if (hif-looking-at-endif)
626 (error "No previous #ifdef")))))
630 "Move point to beginning of nested ifdef or else-part."
632 (let ((start (point)))
633 (hif-find-next-relevant)
634 (if (or (hif-looking-at-ifX) (hif-looking-at-else))
637 (error "No following #ifdef"))))
641 "Move point to beginning of enclosing ifdef or else-part."
644 (let ((start (point)))
645 (if (not (hif-looking-at-endif))
646 (hif-find-previous-relevant))
647 (if (hif-looking-at-endif)
648 (hif-endif-to-ifdef))
649 (if (= start (point))
650 (error "No previous #ifdef"))))
652 (defun next-ifdef (&optional arg)
653 "Move to the beginning of the next #ifX, #else, or #endif.
654 With argument, do this that many times."
656 (or arg (setq arg 1))
658 (previous-ifdef (- arg)))
661 (hif-find-next-relevant)
665 (error "No following #ifdefs, #elses, or #endifs")))))
667 (defun previous-ifdef (&optional arg)
668 "Move to the beginning of the previous #ifX, #else, or #endif.
669 With argument, do this that many times."
671 (or arg (setq arg 1))
673 (next-ifdef (- arg)))
676 (let ((start (point)))
677 (hif-find-previous-relevant)
678 (if (= start (point))
679 (error "No previous #ifdefs, #elses, or #endifs")
683 ;===%%SF%% parsing (End) ===
686 ;===%%SF%% hide-ifdef-hiding (Start) ===
689 ;;; A range is a structure with four components:
690 ;;; ELSE-P True if there was an else clause for the ifdef.
691 ;;; START The start of the range. (beginning of line)
692 ;;; ELSE The else marker (beginning of line)
693 ;;; Only valid if ELSE-P is true.
694 ;;; END The end of the range. (beginning of line)
696 (defun hif-make-range (else-p start end &optional else)
697 (list else-p start else end))
699 (defun hif-range-else-p (range) (elt range 0))
700 (defun hif-range-start (range) (elt range 1))
701 (defun hif-range-else (range) (elt range 2))
702 (defun hif-range-end (range) (elt range 3))
707 ;;; The workhorse, it delimits the #if region. Reasonably simple:
708 ;;; Skip until an #else or #endif is found, remembering positions. If
709 ;;; an #else was found, skip some more, looking for the true #endif.
711 (defun hif-find-range ()
712 "Returns a Range structure describing the current #if region.
713 Point is left unchanged."
714 ; (message "hif-find-range at %d" (point))
717 (let ((start (point))
721 ;; Part one. Look for either #endif or #else.
722 ;; This loop-and-a-half dedicated to E. Dijkstra.
723 (hif-find-next-relevant)
724 (while (hif-looking-at-ifX) ; Skip nested ifdef
726 (hif-find-next-relevant))
727 ;; Found either a #else or an #endif.
728 (cond ((hif-looking-at-else)
732 (setq end (point)) ; (save-excursion (end-of-line) (point))
734 ;; If found #else, look for #endif.
737 (hif-find-next-relevant)
738 (while (hif-looking-at-ifX) ; Skip nested ifdef
740 (hif-find-next-relevant))
741 (if (hif-looking-at-else)
742 (error "Found two elses in a row? Broken!"))
743 (setq end (point)) ; (save-excursion (end-of-line) (point))
745 (hif-make-range else-p start end else))))
749 ;;; NOTE: If there's an #ifdef at the beginning of the file, we can't
750 ;;; hide it. There's no previous newline to replace. If we added
751 ;;; one, we'd throw off all the counts. Feh.
753 (defun hif-hide-line (point)
754 "Hide the line containing point. Does nothing if `hide-ifdef-lines' is nil."
758 (let ((modp (buffer-modified-p)))
762 (if (not (= (point) 1))
763 (hide-ifdef-region (1- (point)) (point))))
764 (set-buffer-modified-p modp))
769 ;;; Hif-Possibly-Hide
770 ;;; There are four cases. The #ifX expression is "taken" if it
771 ;;; the hide-ifdef-evaluator returns T. Presumably, this means the code
772 ;;; inside the #ifdef would be included when the program was
775 ;;; Case 1: #ifX taken, and there's an #else.
776 ;;; The #else part must be hidden. The #if (then) part must be
777 ;;; processed for nested #ifX's.
778 ;;; Case 2: #ifX taken, and there's no #else.
779 ;;; The #if part must be processed for nested #ifX's.
780 ;;; Case 3: #ifX not taken, and there's an #else.
781 ;;; The #if part must be hidden. The #else part must be processed
783 ;;; Case 4: #ifX not taken, and there's no #else.
784 ;;; The #ifX part must be hidden.
786 ;;; Further processing is done by narrowing to the relevant region
787 ;;; and just recursively calling hide-ifdef-guts.
789 ;;; When hif-possibly-hide returns, point is at the end of the
790 ;;; possibly-hidden range.
792 (defun hif-recurse-on (start end)
793 "Call `hide-ifdef-guts' after narrowing to end of START line and END line."
798 (narrow-to-region (point) end)
801 (defun hif-possibly-hide ()
802 "Called at #ifX expression, this hides those parts that should be
803 hidden, according to judgement of `hide-ifdef-evaluator'."
804 ; (message "hif-possibly-hide") (sit-for 1)
805 (let ((test (hif-canonicalize))
806 (range (hif-find-range)))
807 ; (message "test = %s" test) (sit-for 1)
809 (hif-hide-line (hif-range-end range))
810 (if (funcall hide-ifdef-evaluator test)
811 (cond ((hif-range-else-p range) ; case 1
812 (hif-hide-line (hif-range-else range))
813 (hide-ifdef-region (hif-range-else range)
814 (1- (hif-range-end range)))
815 (hif-recurse-on (hif-range-start range)
816 (hif-range-else range)))
818 (hif-recurse-on (hif-range-start range)
819 (hif-range-end range))))
820 (cond ((hif-range-else-p range) ; case 3
821 (hif-hide-line (hif-range-else range))
822 (hide-ifdef-region (hif-range-start range)
823 (1- (hif-range-else range)))
824 (hif-recurse-on (hif-range-else range)
825 (hif-range-end range)))
827 (hide-ifdef-region (point)
828 (1- (hif-range-end range))))
830 (hif-hide-line (hif-range-start range)) ; Always hide start.
831 (goto-char (hif-range-end range))
837 (defun hide-ifdef-guts ()
838 "Does the work of `hide-ifdefs', except for the work that's pointless
839 to redo on a recursive entry."
840 ; (message "hide-ifdef-guts")
842 (goto-char (point-min))
843 (while (hif-find-any-ifX)
844 (hif-possibly-hide))))
846 ;===%%SF%% hide-ifdef-hiding (End) ===
849 ;===%%SF%% exports (Start) ===
852 (defvar hide-ifdef-initially nil
853 "*Non-nil if `hide-ifdefs' should be called when Hide-Ifdef mode
854 is first activated.")
856 (defvar hide-ifdef-hiding nil
857 "Non-nil if text might be hidden.")
860 (defvar hide-ifdef-read-only nil
861 "*Set to non-nil if you want buffer to be read-only while hiding text.")
863 (defvar hif-outside-read-only nil
864 "Internal variable. Saves the value of `buffer-read-only' while hiding.")
867 (defvar hide-ifdef-lines nil
868 "*Set to t if you don't want to see the #ifX, #else, and #endif lines.")
870 (defun hide-ifdef-toggle-read-only ()
871 "Toggle hide-ifdef-read-only."
873 (setq hide-ifdef-read-only (not hide-ifdef-read-only))
874 (message "Hide-Read-Only %s"
875 (if hide-ifdef-read-only "ON" "OFF"))
876 (if hide-ifdef-hiding
877 (setq buffer-read-only (or hide-ifdef-read-only hif-outside-read-only)))
878 (hif-update-mode-line))
880 (defun hide-ifdef-toggle-outside-read-only ()
881 "Replacement for `toggle-read-only' within Hide Ifdef mode."
883 (setq hif-outside-read-only (not hif-outside-read-only))
884 (message "Read only %s"
885 (if hif-outside-read-only "ON" "OFF"))
886 (setq buffer-read-only
887 (or (and hide-ifdef-hiding hide-ifdef-read-only)
888 hif-outside-read-only)
890 (hif-update-mode-line))
893 (defun hide-ifdef-define (var)
894 "Define a VAR so that #ifdef VAR would be included."
895 (interactive "SDefine what? ")
897 (if hide-ifdef-hiding (hide-ifdefs)))
899 (defun hide-ifdef-undef (var)
900 "Undefine a VAR so that #ifdef VAR would not be included."
901 (interactive "SUndefine what? ")
902 (hif-set-var var nil)
903 (if hide-ifdef-hiding (hide-ifdefs)))
906 (defun hide-ifdefs ()
907 "Hide the contents of some #ifdefs.
908 Assume that defined symbols have been added to `hide-ifdef-env'.
909 The text hidden is the text that would not be included by the C
910 preprocessor if it were given the file with those symbols defined.
912 Turn off hiding by calling `show-ifdef'."
915 (message "Hiding...")
916 (if (not hide-ifdef-mode)
917 (hide-ifdef-mode 1)) ; turn on hide-ifdef-mode
918 (if hide-ifdef-hiding
919 (show-ifdefs)) ; Otherwise, deep confusion.
920 (if buffer-read-only (toggle-read-only)) ; make it writable temporarily
921 (setq selective-display t)
922 (setq hide-ifdef-hiding t)
924 (if (or hide-ifdef-read-only hif-outside-read-only)
925 (toggle-read-only)) ; make it read only
926 (message "Hiding done"))
929 (defun show-ifdefs ()
930 "Cancel the effects of `hide-ifdef'. The contents of all #ifdefs is shown."
932 (if buffer-read-only (toggle-read-only)) ; make it writable temporarily
933 (setq selective-display nil) ; defaults
935 (if hif-outside-read-only
936 (toggle-read-only)) ; make it read only
937 (setq hide-ifdef-hiding nil))
940 (defun hif-find-ifdef-block ()
941 "Utility for hide and show `ifdef-block'.
942 Set top and bottom of ifdef block."
946 (if (not (or (hif-looking-at-else) (hif-looking-at-ifX)))
950 (setq max-bottom (1- (point))))
953 (if (not (hif-looking-at-endif))
954 (hif-find-next-relevant))
955 (while (hif-looking-at-ifX)
957 (hif-find-next-relevant))
958 (setq bottom (min max-bottom (1- (point))))))
962 (defun hide-ifdef-block ()
963 "Hide the ifdef block (true or false part) enclosing or before the cursor."
965 (if (not hide-ifdef-mode)
967 (if buffer-read-only (toggle-read-only))
968 (setq selective-display t)
970 (hif-find-ifdef-block) ; set top and bottom - dynamic scoping
971 (hide-ifdef-region top bottom)
975 (hif-hide-line (1+ bottom))))
976 (setq hide-ifdef-hiding t))
977 (if (or hide-ifdef-read-only hif-outside-read-only)
981 (defun show-ifdef-block ()
982 "Show the ifdef block (true or false part) enclosing or before the cursor."
984 (let ((old-read-only buffer-read-only))
985 (if old-read-only (toggle-read-only))
989 (hif-show-ifdef-region (1- (point)) (progn (end-of-line) (point))))
992 (hif-find-ifdef-block)
993 (hif-show-ifdef-region (1- top) bottom))
996 ; restore read only status since we dont know if all is shown.
997 (if old-read-only (toggle-read-only))))
1000 ;;; definition alist support
1002 (defvar hide-ifdef-define-alist nil
1003 "A global assoc list of pre-defined symbol lists")
1005 (defun hif-compress-define-list (env)
1006 "Compress the define list ENV into a list of defined symbols only."
1007 (let ((defs (mapcar '(lambda (arg)
1008 (if (hif-lookup (car arg)) (car arg)))
1013 (setq new-defs (cons (car defs) new-defs)))
1014 (setq defs (cdr defs)))
1017 (defun hide-ifdef-set-define-alist (name)
1018 "Set the association for NAME to `hide-ifdef-env'."
1019 (interactive "SSet define list: ")
1020 (setq hide-ifdef-define-alist
1021 (cons (cons name (hif-compress-define-list hide-ifdef-env))
1022 hide-ifdef-define-alist)))
1024 (defun hide-ifdef-use-define-alist (name)
1025 "Set `hide-ifdef-env' to the define list specified by NAME."
1026 (interactive "SUse define list: ")
1027 (let ((define-list (assoc name hide-ifdef-define-alist)))
1029 (setq hide-ifdef-env
1030 (mapcar '(lambda (arg) (cons arg t))
1032 (error "No define list for %s" name))
1033 (if hide-ifdef-hiding (hide-ifdefs))))
1035 ;;; hideif.el ends here