1 ;;; hideif.el --- hides selected code within ifdef
3 ;; Copyright (C) 1988,1994,2001, 2002 Free Software Foundation, Inc.
5 ;; Author: Daniel LaLiberte <liberte@holonexus.org>
7 ;; Keywords: c, outlines
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software; you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
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.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
28 ;; To initialize, toggle the hide-ifdef minor mode with
30 ;; M-x hide-ifdef-mode
32 ;; This will set up key bindings and call hide-ifdef-mode-hook if it
33 ;; has a value. To explicitly hide ifdefs using a buffer-local
34 ;; define list (default empty), type
36 ;; M-x hide-ifdefs or C-c @ h
38 ;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't
39 ;; pass through. The support of constant expressions in #if lines is
40 ;; limited to identifiers, parens, and the operators: &&, ||, !, and
41 ;; "defined". Please extend this.
43 ;; The hidden code is marked by ellipses (...). Be
44 ;; cautious when editing near ellipses, since the hidden text is
45 ;; still in the buffer, and you can move the point into it and modify
47 ;; You can make your buffer read-only while hide-ifdef-hiding by setting
48 ;; hide-ifdef-read-only to a non-nil value. You can toggle this
49 ;; variable with hide-ifdef-toggle-read-only (C-c @ C-q).
51 ;; You can undo the effect of hide-ifdefs by typing
53 ;; M-x show-ifdefs or C-c @ s
55 ;; Use M-x hide-ifdef-define (C-c @ d) to define a symbol.
56 ;; Use M-x hide-ifdef-undef (C-c @ u) to undefine a symbol.
58 ;; If you define or undefine a symbol while hide-ifdef-mode is in effect,
59 ;; the display will be updated. Only the define list for the current
60 ;; buffer will be affected. You can save changes to the local define
61 ;; list with hide-ifdef-set-define-alist. This adds entries
62 ;; to hide-ifdef-define-alist.
64 ;; If you have defined a hide-ifdef-mode-hook, you can set
65 ;; up a list of symbols that may be used by hide-ifdefs as in the
68 ;; (add-hook 'hide-ifdef-mode-hook
70 ;; (unless hide-ifdef-define-alist
71 ;; (setq hide-ifdef-define-alist
73 ;; (list2 TWO THREE))))
74 ;; (hide-ifdef-use-define-alist 'list2))) ; use list2 by default
76 ;; You can call hide-ifdef-use-define-alist (C-c @ U) at any time to specify
77 ;; another list to use.
79 ;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called,
80 ;; set hide-ifdef-initially to non-nil.
82 ;; If you set hide-ifdef-lines to t, hide-ifdefs hides all the #ifdef lines.
83 ;; In the absence of highlighting, that might be a bad idea. If you set
84 ;; hide-ifdef-lines to nil (the default), the surrounding preprocessor
85 ;; lines will be displayed. That can be confusing in its own
86 ;; right. Other variations on display are possible, but not much
89 ;; You can explicitly hide or show individual ifdef blocks irrespective
90 ;; of the define list by using hide-ifdef-block and show-ifdef-block.
92 ;; You can move the point between ifdefs with forward-ifdef, backward-ifdef,
93 ;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef.
95 ;; If you have minor-mode-alist in your mode line (the default) two labels
96 ;; may appear. "Ifdef" will appear when hide-ifdef-mode is active. "Hiding"
97 ;; will appear when text may be hidden ("hide-ifdef-hiding" is non-nil).
99 ;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL.
100 ;; Extensively modified by Daniel LaLiberte (while at Gould).
102 ;; You may freely modify and distribute this, but keep a record
103 ;; of modifications and send comments to:
104 ;; liberte@a.cs.uiuc.edu or ihnp4!uiucdcs!liberte
105 ;; I will continue to upgrade hide-ifdef-mode
106 ;; with your contributions.
112 (defgroup hide-ifdef nil
113 "Hide selected code within `ifdef'."
116 (defvar hide-ifdef-mode-submap
117 ;; Set up the submap that goes after the prefix key.
118 (let ((map (make-sparse-keymap)))
119 (define-key map
"d" 'hide-ifdef-define
)
120 (define-key map
"u" 'hide-ifdef-undef
)
121 (define-key map
"D" 'hide-ifdef-set-define-alist
)
122 (define-key map
"U" 'hide-ifdef-use-define-alist
)
124 (define-key map
"h" 'hide-ifdefs
)
125 (define-key map
"s" 'show-ifdefs
)
126 (define-key map
"\C-d" 'hide-ifdef-block
)
127 (define-key map
"\C-s" 'show-ifdef-block
)
129 (define-key map
"\C-q" 'hide-ifdef-toggle-read-only
)
130 (substitute-key-definition
131 'toggle-read-only
'hide-ifdef-toggle-outside-read-only map
)
133 "Keymap used by `hide-ifdef-mode' under `hide-ifdef-mode-prefix-key'.")
135 (defconst hide-ifdef-mode-prefix-key
"\C-c@"
136 "Prefix key for all Hide-Ifdef mode commands.")
138 (defvar hide-ifdef-mode-map
139 ;; Set up the mode's main map, which leads via the prefix key to the submap.
140 (let ((map (make-sparse-keymap)))
141 (define-key map hide-ifdef-mode-prefix-key hide-ifdef-mode-submap
)
143 "Keymap used with `hide-ifdef-mode'.")
145 (defvar hide-ifdef-hiding nil
146 "Non-nil when text may be hidden.")
148 (or (assq 'hide-ifdef-hiding minor-mode-alist
)
149 (setq minor-mode-alist
150 (cons '(hide-ifdef-hiding " Hiding")
153 ;; fix c-mode syntax table so we can recognize whole symbols.
154 (defvar hide-ifdef-syntax-table
155 (let ((st (copy-syntax-table c-mode-syntax-table
)))
156 (modify-syntax-entry ?_
"w" st
)
157 (modify-syntax-entry ?
& "." st
)
158 (modify-syntax-entry ?\|
"." st
)
160 "Syntax table used for tokenizing #if expressions.")
162 (defvar hide-ifdef-env nil
163 "An alist of defined symbols and their values.")
165 (defvar hif-outside-read-only nil
166 "Internal variable. Saves the value of `buffer-read-only' while hiding.")
169 (define-minor-mode hide-ifdef-mode
170 "Toggle Hide-Ifdef mode. This is a minor mode, albeit a large one.
171 With ARG, turn Hide-Ifdef mode on if arg is positive, off otherwise.
172 In Hide-Ifdef mode, code within #ifdef constructs that the C preprocessor
173 would eliminate may be hidden from view. Several variables affect
174 how the hiding is done:
177 An association list of defined and undefined symbols for the
178 current buffer. Initially, the global value of `hide-ifdef-env'
181 `hide-ifdef-define-alist'
182 An association list of defined symbol lists.
183 Use `hide-ifdef-set-define-alist' to save the current `hide-ifdef-env'
184 and `hide-ifdef-use-define-alist' to set the current `hide-ifdef-env'
185 from one of the lists in `hide-ifdef-define-alist'.
188 Set to non-nil to not show #if, #ifdef, #ifndef, #else, and
189 #endif lines when hiding.
191 `hide-ifdef-initially'
192 Indicates whether `hide-ifdefs' should be called when Hide-Ifdef mode
195 `hide-ifdef-read-only'
196 Set to non-nil if you want to make buffers read only while hiding.
197 After `show-ifdefs', read-only status is restored to previous value.
199 \\{hide-ifdef-mode-map}"
203 ;; inherit global values
204 (set (make-local-variable 'hide-ifdef-env
)
205 (default-value 'hide-ifdef-env
))
206 (set (make-local-variable 'hide-ifdef-hiding
)
207 (default-value 'hide-ifdef-hiding
))
208 (set (make-local-variable 'hif-outside-read-only
) buffer-read-only
)
209 (set (make-local-variable 'line-move-ignore-invisible
) t
)
210 (add-hook 'change-major-mode-hook
211 (lambda () (hide-ifdef-mode -
1)) nil t
)
213 (add-to-invisibility-spec '(hide-ifdef . t
))
215 (if hide-ifdef-initially
218 ;; else end hide-ifdef-mode
219 (kill-local-variable 'line-move-ignore-invisible
)
220 (remove-from-invisibility-spec '(hide-ifdef . t
))
221 (if hide-ifdef-hiding
225 (defun hif-show-all ()
226 "Show all of the text in the current buffer."
228 (hif-show-ifdef-region (point-min) (point-max)))
230 ;; By putting this on after-revert-hook, we arrange that it only
231 ;; does anything when revert-buffer avoids turning off the mode.
232 ;; (That can happen in VC.)
233 (defun hif-after-revert-function ()
234 (and hide-ifdef-mode hide-ifdef-hiding
236 (add-hook 'after-revert-hook
'hif-after-revert-function
)
238 (defun hif-end-of-line ()
240 (while (= (logand 1 (skip-chars-backward "\\\\")) 1)
243 (defun hide-ifdef-region-internal (start end
)
244 (remove-overlays start end
'invisible
'hide-ifdef
)
245 (let ((o (make-overlay start end
)))
246 (overlay-put o
'invisible
'hide-ifdef
)))
248 (defun hide-ifdef-region (start end
)
249 "START is the start of a #if or #else form. END is the ending part.
250 Everything including these lines is made invisible."
252 (goto-char start
) (hif-end-of-line) (setq start
(point))
253 (goto-char end
) (hif-end-of-line) (setq end
(point))
254 (hide-ifdef-region-internal start end
)))
256 (defun hif-show-ifdef-region (start end
)
257 "Everything between START and END is made visible."
258 (remove-overlays start end
'invisible
'hide-ifdef
))
261 ;;===%%SF%% evaluation (Start) ===
263 ;; It is not useful to set this to anything but `eval'.
264 ;; In fact, the variable might as well be eliminated.
265 (defvar hide-ifdef-evaluator
'eval
266 "The function to use to evaluate a form.
267 The evaluator is given a canonical form and returns t if text under
268 that form should be displayed.")
270 (defvar hif-undefined-symbol nil
271 "...is by default considered to be false.")
274 (defun hif-set-var (var value
)
275 "Prepend (var value) pair to hide-ifdef-env."
276 (setq hide-ifdef-env
(cons (cons var value
) hide-ifdef-env
)))
279 (defun hif-lookup (var)
280 ;; (message "hif-lookup %s" var)
281 (let ((val (assoc var hide-ifdef-env
)))
284 hif-undefined-symbol
)))
286 (defun hif-defined (var)
287 (if (assoc var hide-ifdef-env
) 1 0))
289 ;;===%%SF%% evaluation (End) ===
293 ;;===%%SF%% parsing (Start) ===
294 ;;; The code that understands what ifs and ifdef in files look like.
296 (defconst hif-cpp-prefix
"\\(^\\|\r\\)[ \t]*#[ \t]*")
297 (defconst hif-ifndef-regexp
(concat hif-cpp-prefix
"ifndef"))
298 (defconst hif-ifx-regexp
(concat hif-cpp-prefix
"if\\(n?def\\)?[ \t]+"))
299 (defconst hif-else-regexp
(concat hif-cpp-prefix
"else"))
300 (defconst hif-endif-regexp
(concat hif-cpp-prefix
"endif"))
301 (defconst hif-ifx-else-endif-regexp
302 (concat hif-ifx-regexp
"\\|" hif-else-regexp
"\\|" hif-endif-regexp
))
304 ;; Used to store the current token and the whole token list during parsing.
305 ;; Only bound dynamically.
307 (defvar hif-token-list
)
309 ;; pattern to match initial identifier, !, &&, ||, (, or ).
310 ;; Added ==, + and -: garyo@avs.com 8/9/94
311 (defconst hif-token-regexp
312 "\\(&&\\|||\\|[!=]=\\|!\\|[()+?:-]\\|[<>]=?\\|\\w+\\)")
314 (defun hif-tokenize (start end
)
315 "Separate string between START and END into a list of tokens."
316 (let ((token-list nil
))
317 (with-syntax-table hide-ifdef-syntax-table
320 (while (progn (forward-comment (point-max)) (< (point) end
))
321 ;; (message "expr-start = %d" expr-start) (sit-for 1)
323 ((looking-at "\\\\\n")
326 ((looking-at hif-token-regexp
)
327 (let ((token (buffer-substring (point) (match-end 0))))
328 (goto-char (match-end 0))
329 ;; (message "token: %s" token) (sit-for 1)
331 ((string-equal token
"||") 'or
)
332 ((string-equal token
"&&") 'and
)
333 ((string-equal token
"==") 'equal
)
334 ((string-equal token
"!=") 'hif-notequal
)
335 ((string-equal token
"!") 'not
)
336 ((string-equal token
"defined") 'hif-defined
)
337 ((string-equal token
"(") 'lparen
)
338 ((string-equal token
")") 'rparen
)
339 ((string-equal token
">") 'hif-greater
)
340 ((string-equal token
"<") 'hif-less
)
341 ((string-equal token
">=") 'hif-greater-equal
)
342 ((string-equal token
"<=") 'hif-less-equal
)
343 ((string-equal token
"+") 'hif-plus
)
344 ((string-equal token
"-") 'hif-minus
)
345 ((string-equal token
"?") 'hif-conditional
)
346 ((string-equal token
":") 'hif-colon
)
347 ((string-match "\\`[0-9]*\\'" token
)
348 (string-to-number token
))
351 (t (error "Bad #if expression: %s" (buffer-string)))))))
352 (nreverse token-list
)))
354 ;;;-----------------------------------------------------------------
355 ;;; Translate C preprocessor #if expressions using recursive descent.
356 ;;; This parser is limited to the operators &&, ||, !, and "defined".
357 ;;; Added ==, !=, +, and -. Gary Oberbrunner, garyo@avs.com, 8/9/94
359 (defsubst hif-nexttoken
()
360 "Pop the next token from token-list into the let variable \"hif-token\"."
361 (setq hif-token
(pop hif-token-list
)))
363 (defun hif-parse-if-exp (hif-token-list)
364 "Parse the TOKEN-LIST. Return translated list in prefix form."
368 (if hif-token
; is there still a token?
369 (error "Error: unexpected token: %s" hif-token
))))
372 "Parse an expression as found in #if.
373 expr : or-expr | or-expr '?' expr ':' expr."
374 (let ((result (hif-or-expr))
376 (while (eq hif-token
'hif-conditional
)
378 (setq middle
(hif-expr))
379 (if (eq hif-token
'hif-colon
)
382 (setq result
(list 'hif-conditional result middle
(hif-expr))))
383 (error "Error: unexpected token: %s" hif-token
)))
386 (defun hif-or-expr ()
387 "Parse n or-expr : and-expr | or-expr '||' and-expr."
388 (let ((result (hif-and-expr)))
389 (while (eq hif-token
'or
)
391 (setq result
(list 'hif-or result
(hif-and-expr))))
394 (defun hif-and-expr ()
395 "Parse an and-expr : eq-expr | and-expr '&&' eq-expr."
396 (let ((result (hif-eq-expr)))
397 (while (eq hif-token
'and
)
399 (setq result
(list 'hif-and result
(hif-eq-expr))))
402 (defun hif-eq-expr ()
403 "Parse an eq-expr : math | eq-expr `=='|`!='|`<'|`>'|`>='|`<=' math."
404 (let ((result (hif-math))
406 (while (memq hif-token
'(equal hif-notequal hif-greater hif-less
407 hif-greater-equal hif-less-equal
))
408 (setq eq-token hif-token
)
410 (setq result
(list eq-token result
(hif-math))))
414 "Parse an expression with + or - and simpler things.
415 math : factor | math '+|-' factor."
416 (let ((result (hif-factor))
418 (while (memq hif-token
'(hif-plus hif-minus
))
419 (setq math-op hif-token
)
421 (setq result
(list math-op result
(hif-factor))))
425 "Parse a factor: '!' factor | '(' expr ')' | 'defined(' id ')' | id."
429 (list 'hif-not
(hif-factor)))
431 ((eq hif-token
'lparen
)
433 (let ((result (hif-expr)))
434 (if (not (eq hif-token
'rparen
))
435 (error "Bad token in parenthesized expression: %s" hif-token
)
439 ((eq hif-token
'hif-defined
)
441 (let ((paren (when (eq hif-token
'lparen
) (hif-nexttoken) t
))
443 (if (memq hif-token
'(or and not hif-defined lparen rparen
))
444 (error "Error: unexpected token: %s" hif-token
))
447 (unless (eq hif-token
'rparen
)
448 (error "Error: expected \")\" after identifier")))
450 `(hif-defined (quote ,ident
))))
453 (prog1 hif-token
(hif-nexttoken)))
456 (let ((ident hif-token
))
457 (if (memq ident
'(or and
))
458 (error "Error: missing identifier"))
460 `(hif-lookup (quote ,ident
))))))
462 (defun hif-mathify (val)
463 "Treat VAL as a number: if it's t or nil, use 1 or 0."
468 (defun hif-conditional (a b c
)
469 (if (not (zerop (hif-mathify a
))) (hif-mathify b
) (hif-mathify c
)))
471 (and (not (zerop (hif-mathify a
))) (not (zerop (hif-mathify b
)))))
473 (or (not (zerop (hif-mathify a
))) (not (zerop (hif-mathify b
)))))
475 (zerop (hif-mathify a
)))
476 (defun hif-plus (a b
)
477 "Like ordinary plus but treat t and nil as 1 and 0."
478 (+ (hif-mathify a
) (hif-mathify b
)))
479 (defun hif-minus (a b
)
480 "Like ordinary minus but treat t and nil as 1 and 0."
481 (- (hif-mathify a
) (hif-mathify b
)))
482 (defun hif-notequal (a b
)
483 "Like (not (equal A B)) but as one symbol."
485 (defun hif-greater (a b
)
487 (> (hif-mathify a
) (hif-mathify b
)))
488 (defun hif-less (a b
)
490 (< (hif-mathify a
) (hif-mathify b
)))
491 (defun hif-greater-equal (a b
)
493 (>= (hif-mathify a
) (hif-mathify b
)))
494 (defun hif-less-equal (a b
)
496 (<= (hif-mathify a
) (hif-mathify b
)))
497 ;;;----------- end of parser -----------------------
500 (defun hif-canonicalize ()
501 "When at beginning of #ifX, return a Lisp expression for its condition."
503 (let ((negate (looking-at hif-ifndef-regexp
)))
504 (re-search-forward hif-ifx-regexp
)
505 (let* ((tokens (hif-tokenize (point)
506 (progn (hif-end-of-line) (point))))
507 (expr (hif-parse-if-exp tokens
)))
508 ;; (message "hif-canonicalized: %s" expr)
514 (defun hif-find-any-ifX ()
515 "Move to next #if..., or #ifndef, at point or after."
516 ;; (message "find ifX at %d" (point))
518 (re-search-forward hif-ifx-regexp
(point-max) t
)
519 (beginning-of-line)))
522 (defun hif-find-next-relevant ()
523 "Move to next #if..., #else, or #endif, after the current line."
524 ;; (message "hif-find-next-relevant at %d" (point))
526 ;; avoid infinite recursion by only going to beginning of line if match found
527 (if (re-search-forward hif-ifx-else-endif-regexp
(point-max) t
)
528 (beginning-of-line)))
530 (defun hif-find-previous-relevant ()
531 "Move to previous #if..., #else, or #endif, before the current line."
532 ;; (message "hif-find-previous-relevant at %d" (point))
534 ;; avoid infinite recursion by only going to beginning of line if match found
535 (if (re-search-backward hif-ifx-else-endif-regexp
(point-min) t
)
536 (beginning-of-line)))
539 (defun hif-looking-at-ifX () ;; Should eventually see #if
540 (looking-at hif-ifx-regexp
))
541 (defun hif-looking-at-endif ()
542 (looking-at hif-endif-regexp
))
543 (defun hif-looking-at-else ()
544 (looking-at hif-else-regexp
))
548 (defun hif-ifdef-to-endif ()
549 "If positioned at #ifX or #else form, skip to corresponding #endif."
550 ;; (message "hif-ifdef-to-endif at %d" (point)) (sit-for 1)
551 (hif-find-next-relevant)
552 (cond ((hif-looking-at-ifX)
553 (hif-ifdef-to-endif) ; find endif of nested if
554 (hif-ifdef-to-endif)) ; find outer endif or else
555 ((hif-looking-at-else)
556 (hif-ifdef-to-endif)) ; find endif following else
557 ((hif-looking-at-endif)
560 (error "Mismatched #ifdef #endif pair"))))
563 (defun hif-endif-to-ifdef ()
564 "If positioned at #endif form, skip backward to corresponding #ifX."
565 ;; (message "hif-endif-to-ifdef at %d" (point))
566 (let ((start (point)))
567 (hif-find-previous-relevant)
568 (if (= start
(point))
569 (error "Mismatched #ifdef #endif pair")))
570 (cond ((hif-looking-at-endif)
571 (hif-endif-to-ifdef) ; find beginning of nested if
572 (hif-endif-to-ifdef)) ; find beginning of outer if or else
573 ((hif-looking-at-else)
574 (hif-endif-to-ifdef))
575 ((hif-looking-at-ifX)
577 (t))) ; never gets here
580 (defun forward-ifdef (&optional arg
)
581 "Move point to beginning of line of the next ifdef-endif.
582 With argument, do this that many times."
584 (or arg
(setq arg
1))
585 (if (< arg
0) (backward-ifdef (- arg
))
588 (let ((start (point)))
589 (unless (hif-looking-at-ifX)
590 (hif-find-next-relevant))
591 (if (hif-looking-at-ifX)
594 (error "No following #ifdef"))))))
597 (defun backward-ifdef (&optional arg
)
598 "Move point to beginning of the previous ifdef-endif.
599 With argument, do this that many times."
601 (or arg
(setq arg
1))
602 (if (< arg
0) (forward-ifdef (- arg
))
606 (let ((start (point)))
607 (unless (hif-looking-at-endif)
608 (hif-find-previous-relevant))
609 (if (hif-looking-at-endif)
612 (error "No previous #ifdef"))))))
616 "Move point to beginning of nested ifdef or else-part."
618 (let ((start (point)))
619 (hif-find-next-relevant)
620 (if (or (hif-looking-at-ifX) (hif-looking-at-else))
623 (error "No following #ifdef"))))
627 "Move point to beginning of enclosing ifdef or else-part."
630 (let ((start (point)))
631 (unless (hif-looking-at-endif)
632 (hif-find-previous-relevant))
633 (if (hif-looking-at-endif)
634 (hif-endif-to-ifdef))
635 (if (= start
(point))
636 (error "No previous #ifdef"))))
638 (defun next-ifdef (&optional arg
)
639 "Move to the beginning of the next #ifX, #else, or #endif.
640 With argument, do this that many times."
642 (or arg
(setq arg
1))
643 (if (< arg
0) (previous-ifdef (- arg
))
646 (hif-find-next-relevant)
649 (error "No following #ifdefs, #elses, or #endifs")))))
651 (defun previous-ifdef (&optional arg
)
652 "Move to the beginning of the previous #ifX, #else, or #endif.
653 With argument, do this that many times."
655 (or arg
(setq arg
1))
656 (if (< arg
0) (next-ifdef (- arg
))
659 (let ((start (point)))
660 (hif-find-previous-relevant)
661 (if (= start
(point))
662 (error "No previous #ifdefs, #elses, or #endifs"))))))
665 ;;===%%SF%% parsing (End) ===
668 ;;===%%SF%% hide-ifdef-hiding (Start) ===
671 ;;; A range is a structure with four components:
672 ;;; ELSE-P True if there was an else clause for the ifdef.
673 ;;; START The start of the range. (beginning of line)
674 ;;; ELSE The else marker (beginning of line)
675 ;;; Only valid if ELSE-P is true.
676 ;;; END The end of the range. (beginning of line)
678 (defsubst hif-make-range
(start end
&optional else
)
679 (list start else end
))
681 (defsubst hif-range-start
(range) (elt range
0))
682 (defsubst hif-range-else
(range) (elt range
1))
683 (defsubst hif-range-end
(range) (elt range
2))
688 ;;; The workhorse, it delimits the #if region. Reasonably simple:
689 ;;; Skip until an #else or #endif is found, remembering positions. If
690 ;;; an #else was found, skip some more, looking for the true #endif.
692 (defun hif-find-range ()
693 "Return a Range structure describing the current #if region.
694 Point is left unchanged."
695 ;; (message "hif-find-range at %d" (point))
698 (let ((start (point))
701 ;; Part one. Look for either #endif or #else.
702 ;; This loop-and-a-half dedicated to E. Dijkstra.
704 (hif-find-next-relevant)
705 (hif-looking-at-ifX)) ; Skip nested ifdef
706 (hif-ifdef-to-endif))
707 ;; Found either a #else or an #endif.
708 (cond ((hif-looking-at-else)
711 (setq end
(point)))) ; (save-excursion (end-of-line) (point))
712 ;; If found #else, look for #endif.
715 (hif-find-next-relevant)
716 (hif-looking-at-ifX)) ; Skip nested ifdef
717 (hif-ifdef-to-endif))
718 (if (hif-looking-at-else)
719 (error "Found two elses in a row? Broken!"))
720 (setq end
(point))) ; (save-excursion (end-of-line) (point))
721 (hif-make-range start end else
))))
726 (defun hif-hide-line (point)
727 "Hide the line containing point. Does nothing if `hide-ifdef-lines' is nil."
731 (hide-ifdef-region-internal (line-beginning-position)
732 (progn (hif-end-of-line) (point))))))
735 ;;; Hif-Possibly-Hide
736 ;;; There are four cases. The #ifX expression is "taken" if it
737 ;;; the hide-ifdef-evaluator returns T. Presumably, this means the code
738 ;;; inside the #ifdef would be included when the program was
741 ;;; Case 1: #ifX taken, and there's an #else.
742 ;;; The #else part must be hidden. The #if (then) part must be
743 ;;; processed for nested #ifX's.
744 ;;; Case 2: #ifX taken, and there's no #else.
745 ;;; The #if part must be processed for nested #ifX's.
746 ;;; Case 3: #ifX not taken, and there's an #else.
747 ;;; The #if part must be hidden. The #else part must be processed
749 ;;; Case 4: #ifX not taken, and there's no #else.
750 ;;; The #ifX part must be hidden.
752 ;;; Further processing is done by narrowing to the relevant region
753 ;;; and just recursively calling hide-ifdef-guts.
755 ;;; When hif-possibly-hide returns, point is at the end of the
756 ;;; possibly-hidden range.
758 (defun hif-recurse-on (start end
)
759 "Call `hide-ifdef-guts' after narrowing to end of START line and END line."
764 (narrow-to-region (point) end
)
767 (defun hif-possibly-hide ()
768 "Called at #ifX expression, this hides those parts that should be hidden.
769 It uses the judgement of `hide-ifdef-evaluator'."
770 ;; (message "hif-possibly-hide") (sit-for 1)
771 (let ((test (hif-canonicalize))
772 (range (hif-find-range)))
773 ;; (message "test = %s" test) (sit-for 1)
775 (hif-hide-line (hif-range-end range
))
776 (if (not (hif-not (funcall hide-ifdef-evaluator test
)))
777 (cond ((hif-range-else range
) ; case 1
778 (hif-hide-line (hif-range-else range
))
779 (hide-ifdef-region (hif-range-else range
)
780 (1- (hif-range-end range
)))
781 (hif-recurse-on (hif-range-start range
)
782 (hif-range-else range
)))
784 (hif-recurse-on (hif-range-start range
)
785 (hif-range-end range
))))
786 (cond ((hif-range-else range
) ; case 3
787 (hif-hide-line (hif-range-else range
))
788 (hide-ifdef-region (hif-range-start range
)
789 (1- (hif-range-else range
)))
790 (hif-recurse-on (hif-range-else range
)
791 (hif-range-end range
)))
793 (hide-ifdef-region (point)
794 (1- (hif-range-end range
))))))
795 (hif-hide-line (hif-range-start range
)) ; Always hide start.
796 (goto-char (hif-range-end range
))
801 (defun hide-ifdef-guts ()
802 "Does most of the work of `hide-ifdefs'.
803 It does not do the work that's pointless to redo on a recursive entry."
804 ;; (message "hide-ifdef-guts")
806 (goto-char (point-min))
807 (while (hif-find-any-ifX)
808 (hif-possibly-hide))))
810 ;;===%%SF%% hide-ifdef-hiding (End) ===
813 ;;===%%SF%% exports (Start) ===
816 (defcustom hide-ifdef-initially nil
817 "*Non-nil means call `hide-ifdefs' when Hide-Ifdef mode is first activated."
822 (defcustom hide-ifdef-read-only nil
823 "*Set to non-nil if you want buffer to be read-only while hiding text."
828 (defcustom hide-ifdef-lines nil
829 "*Non-nil means hide the #ifX, #else, and #endif lines."
833 (defun hide-ifdef-toggle-read-only ()
834 "Toggle `hide-ifdef-read-only'."
836 (setq hide-ifdef-read-only
(not hide-ifdef-read-only
))
837 (message "Hide-Read-Only %s"
838 (if hide-ifdef-read-only
"ON" "OFF"))
839 (if hide-ifdef-hiding
840 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
)))
841 (force-mode-line-update))
843 (defun hide-ifdef-toggle-outside-read-only ()
844 "Replacement for `toggle-read-only' within Hide-Ifdef mode."
846 (setq hif-outside-read-only
(not hif-outside-read-only
))
847 (message "Read only %s"
848 (if hif-outside-read-only
"ON" "OFF"))
849 (setq buffer-read-only
850 (or (and hide-ifdef-hiding hide-ifdef-read-only
)
851 hif-outside-read-only
))
852 (force-mode-line-update))
855 (defun hide-ifdef-define (var)
856 "Define a VAR so that #ifdef VAR would be included."
857 (interactive "SDefine what? ")
859 (if hide-ifdef-hiding
(hide-ifdefs)))
861 (defun hide-ifdef-undef (var)
862 "Undefine a VAR so that #ifdef VAR would not be included."
863 (interactive "SUndefine what? ")
864 (hif-set-var var nil
)
865 (if hide-ifdef-hiding
(hide-ifdefs)))
868 (defun hide-ifdefs (&optional nomsg
)
869 "Hide the contents of some #ifdefs.
870 Assume that defined symbols have been added to `hide-ifdef-env'.
871 The text hidden is the text that would not be included by the C
872 preprocessor if it were given the file with those symbols defined.
874 Turn off hiding by calling `show-ifdefs'."
877 (message "Hiding...")
878 (setq hif-outside-read-only buffer-read-only
)
879 (unless hide-ifdef-mode
(hide-ifdef-mode 1)) ; turn on hide-ifdef-mode
880 (if hide-ifdef-hiding
881 (show-ifdefs)) ; Otherwise, deep confusion.
882 (setq hide-ifdef-hiding t
)
884 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
))
886 (message "Hiding done")))
889 (defun show-ifdefs ()
890 "Cancel the effects of `hide-ifdef': show the contents of all #ifdefs."
892 (setq buffer-read-only hif-outside-read-only
)
894 (setq hide-ifdef-hiding nil
))
897 (defun hif-find-ifdef-block ()
898 "Utility for hide and show `ifdef-block'.
899 Return as (TOP . BOTTOM) the extent of ifdef block."
901 (cons (save-excursion
903 (unless (or (hif-looking-at-else) (hif-looking-at-ifX))
907 (setq max-bottom
(1- (point)))))
910 (unless (hif-looking-at-endif)
911 (hif-find-next-relevant))
912 (while (hif-looking-at-ifX)
914 (hif-find-next-relevant))
915 (min max-bottom
(1- (point)))))))
918 (defun hide-ifdef-block ()
919 "Hide the ifdef block (true or false part) enclosing or before the cursor."
921 (unless hide-ifdef-mode
(hide-ifdef-mode 1))
922 (let ((top-bottom (hif-find-ifdef-block)))
923 (hide-ifdef-region (car top-bottom
) (cdr top-bottom
))
924 (when hide-ifdef-lines
925 (hif-hide-line (car top-bottom
))
926 (hif-hide-line (1+ (cdr top-bottom
))))
927 (setq hide-ifdef-hiding t
))
928 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
)))
931 (defun show-ifdef-block ()
932 "Show the ifdef block (true or false part) enclosing or before the cursor."
937 (hif-show-ifdef-region (1- (point)) (progn (end-of-line) (point))))
938 (let ((top-bottom (hif-find-ifdef-block)))
939 (hif-show-ifdef-region (1- (car top-bottom
)) (cdr top-bottom
)))))
942 ;;; definition alist support
944 (defvar hide-ifdef-define-alist nil
945 "A global assoc list of pre-defined symbol lists.")
947 (defun hif-compress-define-list (env)
948 "Compress the define list ENV into a list of defined symbols only."
949 (let ((new-defs nil
))
950 (dolist (def env new-defs
)
951 (if (hif-lookup (car def
)) (push (car env
) new-defs
)))))
953 (defun hide-ifdef-set-define-alist (name)
954 "Set the association for NAME to `hide-ifdef-env'."
955 (interactive "SSet define list: ")
956 (push (cons name
(hif-compress-define-list hide-ifdef-env
))
957 hide-ifdef-define-alist
))
959 (defun hide-ifdef-use-define-alist (name)
960 "Set `hide-ifdef-env' to the define list specified by NAME."
961 (interactive "SUse define list: ")
962 (let ((define-list (assoc name hide-ifdef-define-alist
)))
965 (mapcar (lambda (arg) (cons arg t
))
967 (error "No define list for %s" name
))
968 (if hide-ifdef-hiding
(hide-ifdefs))))
972 ;;; hideif.el ends here