1 ;;; hideif.el --- hides selected code within ifdef
3 ;; Copyright (C) 1988, 1994, 2001-2011 Free Software Foundation, Inc.
5 ;; Author: Brian Marick
6 ;; Daniel LaLiberte <liberte@holonexus.org>
8 ;; Keywords: c, outlines
10 ;; This file is part of GNU Emacs.
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 3 of the License, or
15 ;; (at your option) any later version.
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.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
27 ;; To initialize, toggle the hide-ifdef minor mode with
29 ;; M-x hide-ifdef-mode
31 ;; This will set up key bindings and call hide-ifdef-mode-hook if it
32 ;; has a value. To explicitly hide ifdefs using a buffer-local
33 ;; define list (default empty), type
35 ;; M-x hide-ifdefs or C-c @ h
37 ;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't
38 ;; pass through. The support of constant expressions in #if lines is
39 ;; limited to identifiers, parens, and the operators: &&, ||, !, and
40 ;; "defined". Please extend this.
42 ;; The hidden code is marked by ellipses (...). Be
43 ;; cautious when editing near ellipses, since the hidden text is
44 ;; still in the buffer, and you can move the point into it and modify
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
67 ;; (add-hook 'hide-ifdef-mode-hook
69 ;; (unless hide-ifdef-define-alist
70 ;; (setq hide-ifdef-define-alist
72 ;; (list2 TWO THREE))))
73 ;; (hide-ifdef-use-define-alist 'list2))) ; use list2 by default
75 ;; You can call hide-ifdef-use-define-alist (C-c @ U) at any time to specify
76 ;; another list to use.
78 ;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called,
79 ;; set hide-ifdef-initially to non-nil.
81 ;; If you set hide-ifdef-lines to t, hide-ifdefs hides all the #ifdef lines.
82 ;; In the absence of highlighting, that might be a bad idea. If you set
83 ;; hide-ifdef-lines to nil (the default), the surrounding preprocessor
84 ;; lines will be displayed. That can be confusing in its own
85 ;; right. Other variations on display are possible, but not much
88 ;; You can explicitly hide or show individual ifdef blocks irrespective
89 ;; of the define list by using hide-ifdef-block and show-ifdef-block.
91 ;; You can move the point between ifdefs with forward-ifdef, backward-ifdef,
92 ;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef.
94 ;; If you have minor-mode-alist in your mode line (the default) two labels
95 ;; may appear. "Ifdef" will appear when hide-ifdef-mode is active. "Hiding"
96 ;; will appear when text may be hidden ("hide-ifdef-hiding" is non-nil).
98 ;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL.
99 ;; Extensively modified by Daniel LaLiberte (while at Gould).
105 (defgroup hide-ifdef nil
106 "Hide selected code within `ifdef'."
109 (defcustom hide-ifdef-initially nil
110 "Non-nil means call `hide-ifdefs' when Hide-Ifdef mode is first activated."
114 (defcustom hide-ifdef-read-only nil
115 "Set to non-nil if you want buffer to be read-only while hiding text."
119 (defcustom hide-ifdef-lines nil
120 "Non-nil means hide the #ifX, #else, and #endif lines."
124 (defcustom hide-ifdef-shadow nil
125 "Non-nil means shadow text instead of hiding it."
130 (defface hide-ifdef-shadow
'((t (:inherit shadow
)))
131 "Face for shadowing ifdef blocks."
136 (defvar hide-ifdef-mode-submap
137 ;; Set up the submap that goes after the prefix key.
138 (let ((map (make-sparse-keymap)))
139 (define-key map
"d" 'hide-ifdef-define
)
140 (define-key map
"u" 'hide-ifdef-undef
)
141 (define-key map
"D" 'hide-ifdef-set-define-alist
)
142 (define-key map
"U" 'hide-ifdef-use-define-alist
)
144 (define-key map
"h" 'hide-ifdefs
)
145 (define-key map
"s" 'show-ifdefs
)
146 (define-key map
"\C-d" 'hide-ifdef-block
)
147 (define-key map
"\C-s" 'show-ifdef-block
)
149 (define-key map
"\C-q" 'hide-ifdef-toggle-read-only
)
150 (define-key map
"\C-w" 'hide-ifdef-toggle-shadowing
)
151 (substitute-key-definition
152 'toggle-read-only
'hide-ifdef-toggle-outside-read-only map
)
154 "Keymap used by `hide-ifdef-mode' under `hide-ifdef-mode-prefix-key'.")
156 (defconst hide-ifdef-mode-prefix-key
"\C-c@"
157 "Prefix key for all Hide-Ifdef mode commands.")
159 (defvar hide-ifdef-mode-map
160 ;; Set up the mode's main map, which leads via the prefix key to the submap.
161 (let ((map (make-sparse-keymap)))
162 (define-key map hide-ifdef-mode-prefix-key hide-ifdef-mode-submap
)
164 "Keymap used with `hide-ifdef-mode'.")
166 (easy-menu-define hide-ifdef-mode-menu hide-ifdef-mode-map
167 "Menu for `hide-ifdef-mode'."
169 ["Hide some ifdefs" hide-ifdefs
170 :help
"Hide the contents of some #ifdefs"]
171 ["Show all ifdefs" show-ifdefs
172 :help
"Cancel the effects of `hide-ifdef': show the contents of all #ifdefs"]
173 ["Hide ifdef block" hide-ifdef-block
174 :help
"Hide the ifdef block (true or false part) enclosing or before the cursor"]
175 ["Show ifdef block" show-ifdef-block
176 :help
"Show the ifdef block (true or false part) enclosing or before the cursor"]
177 ["Define a variable..." hide-ifdef-define
178 :help
"Define a VAR so that #ifdef VAR would be included"]
179 ["Undefine a variable..." hide-ifdef-undef
180 :help
"Undefine a VAR so that #ifdef VAR would not be included"]
181 ["Define an alist..." hide-ifdef-set-define-alist
182 :help
"Set the association for NAME to `hide-ifdef-env'"]
183 ["Use an alist..." hide-ifdef-use-define-alist
184 :help
"Set `hide-ifdef-env' to the define list specified by NAME"]
185 ["Toggle read only" hide-ifdef-toggle-read-only
186 :style toggle
:selected hide-ifdef-read-only
187 :help
"Buffer should be read-only while hiding text"]
188 ["Toggle shadowing" hide-ifdef-toggle-shadowing
189 :style toggle
:selected hide-ifdef-shadow
190 :help
"Text should be shadowed instead of hidden"]))
192 (defvar hide-ifdef-hiding nil
193 "Non-nil when text may be hidden.")
195 (or (assq 'hide-ifdef-hiding minor-mode-alist
)
196 (setq minor-mode-alist
197 (cons '(hide-ifdef-hiding " Hiding")
200 ;; fix c-mode syntax table so we can recognize whole symbols.
201 (defvar hide-ifdef-syntax-table
202 (let ((st (copy-syntax-table c-mode-syntax-table
)))
203 (modify-syntax-entry ?_
"w" st
)
204 (modify-syntax-entry ?
& "." st
)
205 (modify-syntax-entry ?\|
"." st
)
207 "Syntax table used for tokenizing #if expressions.")
209 (defvar hide-ifdef-env nil
210 "An alist of defined symbols and their values.")
212 (defvar hif-outside-read-only nil
213 "Internal variable. Saves the value of `buffer-read-only' while hiding.")
216 (define-minor-mode hide-ifdef-mode
217 "Toggle Hide-Ifdef mode. This is a minor mode, albeit a large one.
218 With ARG, turn Hide-Ifdef mode on if arg is positive, off otherwise.
219 In Hide-Ifdef mode, code within #ifdef constructs that the C preprocessor
220 would eliminate may be hidden from view. Several variables affect
221 how the hiding is done:
224 An association list of defined and undefined symbols for the
225 current buffer. Initially, the global value of `hide-ifdef-env'
228 `hide-ifdef-define-alist'
229 An association list of defined symbol lists.
230 Use `hide-ifdef-set-define-alist' to save the current `hide-ifdef-env'
231 and `hide-ifdef-use-define-alist' to set the current `hide-ifdef-env'
232 from one of the lists in `hide-ifdef-define-alist'.
235 Set to non-nil to not show #if, #ifdef, #ifndef, #else, and
236 #endif lines when hiding.
238 `hide-ifdef-initially'
239 Indicates whether `hide-ifdefs' should be called when Hide-Ifdef mode
242 `hide-ifdef-read-only'
243 Set to non-nil if you want to make buffers read only while hiding.
244 After `show-ifdefs', read-only status is restored to previous value.
246 \\{hide-ifdef-mode-map}"
247 :group
'hide-ifdef
:lighter
" Ifdef"
250 ;; inherit global values
251 (set (make-local-variable 'hide-ifdef-env
)
252 (default-value 'hide-ifdef-env
))
253 (set (make-local-variable 'hide-ifdef-hiding
)
254 (default-value 'hide-ifdef-hiding
))
255 (set (make-local-variable 'hif-outside-read-only
) buffer-read-only
)
256 (set (make-local-variable 'line-move-ignore-invisible
) t
)
257 (add-hook 'change-major-mode-hook
258 (lambda () (hide-ifdef-mode -
1)) nil t
)
260 (add-to-invisibility-spec '(hide-ifdef . t
))
262 (if hide-ifdef-initially
265 ;; else end hide-ifdef-mode
266 (kill-local-variable 'line-move-ignore-invisible
)
267 (remove-from-invisibility-spec '(hide-ifdef . t
))
268 (when hide-ifdef-hiding
272 (defun hif-show-all ()
273 "Show all of the text in the current buffer."
275 (hif-show-ifdef-region (point-min) (point-max)))
277 ;; By putting this on after-revert-hook, we arrange that it only
278 ;; does anything when revert-buffer avoids turning off the mode.
279 ;; (That can happen in VC.)
280 (defun hif-after-revert-function ()
281 (and hide-ifdef-mode hide-ifdef-hiding
283 (add-hook 'after-revert-hook
'hif-after-revert-function
)
285 (defun hif-end-of-line ()
287 (while (= (logand 1 (skip-chars-backward "\\\\")) 1)
290 (defun hide-ifdef-region-internal (start end
)
291 (remove-overlays start end
'hide-ifdef t
)
292 (let ((o (make-overlay start end
)))
293 (overlay-put o
'hide-ifdef t
)
294 (if hide-ifdef-shadow
295 (overlay-put o
'face
'hide-ifdef-shadow
)
296 (overlay-put o
'invisible
'hide-ifdef
))))
298 (defun hide-ifdef-region (start end
)
299 "START is the start of a #if or #else form. END is the ending part.
300 Everything including these lines is made invisible."
302 (goto-char start
) (hif-end-of-line) (setq start
(point))
303 (goto-char end
) (hif-end-of-line) (setq end
(point))
304 (hide-ifdef-region-internal start end
)))
306 (defun hif-show-ifdef-region (start end
)
307 "Everything between START and END is made visible."
308 (remove-overlays start end
'hide-ifdef t
))
311 ;;===%%SF%% evaluation (Start) ===
313 ;; It is not useful to set this to anything but `eval'.
314 ;; In fact, the variable might as well be eliminated.
315 (defvar hide-ifdef-evaluator
'eval
316 "The function to use to evaluate a form.
317 The evaluator is given a canonical form and returns t if text under
318 that form should be displayed.")
320 (defvar hif-undefined-symbol nil
321 "...is by default considered to be false.")
324 (defun hif-set-var (var value
)
325 "Prepend (var value) pair to hide-ifdef-env."
326 (setq hide-ifdef-env
(cons (cons var value
) hide-ifdef-env
)))
329 (defun hif-lookup (var)
330 ;; (message "hif-lookup %s" var)
331 (let ((val (assoc var hide-ifdef-env
)))
334 hif-undefined-symbol
)))
336 (defun hif-defined (var)
337 (if (assoc var hide-ifdef-env
) 1 0))
339 ;;===%%SF%% evaluation (End) ===
343 ;;===%%SF%% parsing (Start) ===
344 ;;; The code that understands what ifs and ifdef in files look like.
346 (defconst hif-cpp-prefix
"\\(^\\|\r\\)[ \t]*#[ \t]*")
347 (defconst hif-ifndef-regexp
(concat hif-cpp-prefix
"ifndef"))
348 (defconst hif-ifx-regexp
(concat hif-cpp-prefix
"if\\(n?def\\)?[ \t]+"))
349 (defconst hif-else-regexp
(concat hif-cpp-prefix
"else"))
350 (defconst hif-endif-regexp
(concat hif-cpp-prefix
"endif"))
351 (defconst hif-ifx-else-endif-regexp
352 (concat hif-ifx-regexp
"\\|" hif-else-regexp
"\\|" hif-endif-regexp
))
354 ;; Used to store the current token and the whole token list during parsing.
355 ;; Only bound dynamically.
357 (defvar hif-token-list
)
359 (defconst hif-token-alist
365 ("!=" . hif-notequal
)
371 (">=" . hif-greater-equal
)
372 ("<=" . hif-less-equal
)
375 ("?" . hif-conditional
)
378 (defconst hif-token-regexp
379 (concat (regexp-opt (mapcar 'car hif-token-alist
)) "\\|\\w+"))
381 (defun hif-tokenize (start end
)
382 "Separate string between START and END into a list of tokens."
383 (let ((token-list nil
))
384 (with-syntax-table hide-ifdef-syntax-table
387 (while (progn (forward-comment (point-max)) (< (point) end
))
388 ;; (message "expr-start = %d" expr-start) (sit-for 1)
390 ((looking-at "\\\\\n")
393 ((looking-at hif-token-regexp
)
394 (let ((token (buffer-substring (point) (match-end 0))))
395 (goto-char (match-end 0))
396 ;; (message "token: %s" token) (sit-for 1)
397 (push (or (cdr (assoc token hif-token-alist
))
398 (if (string-equal token
"defined") 'hif-defined
)
399 (if (string-match "\\`[0-9]*\\'" token
)
400 (string-to-number token
))
403 (t (error "Bad #if expression: %s" (buffer-string)))))))
404 (nreverse token-list
)))
406 ;;;-----------------------------------------------------------------
407 ;;; Translate C preprocessor #if expressions using recursive descent.
408 ;;; This parser is limited to the operators &&, ||, !, and "defined".
409 ;;; Added ==, !=, +, and -. Gary Oberbrunner, garyo@avs.com, 8/9/94
411 (defsubst hif-nexttoken
()
412 "Pop the next token from token-list into the let variable \"hif-token\"."
413 (setq hif-token
(pop hif-token-list
)))
415 (defun hif-parse-if-exp (token-list)
416 "Parse the TOKEN-LIST. Return translated list in prefix form."
417 (let ((hif-token-list token-list
))
421 (if hif-token
; is there still a token?
422 (error "Error: unexpected token: %s" hif-token
)))))
425 "Parse an expression as found in #if.
426 expr : or-expr | or-expr '?' expr ':' expr."
427 (let ((result (hif-or-expr))
429 (while (eq hif-token
'hif-conditional
)
431 (setq middle
(hif-expr))
432 (if (eq hif-token
'hif-colon
)
435 (setq result
(list 'hif-conditional result middle
(hif-expr))))
436 (error "Error: unexpected token: %s" hif-token
)))
439 (defun hif-or-expr ()
440 "Parse n or-expr : and-expr | or-expr '||' and-expr."
441 (let ((result (hif-and-expr)))
442 (while (eq hif-token
'or
)
444 (setq result
(list 'hif-or result
(hif-and-expr))))
447 (defun hif-and-expr ()
448 "Parse an and-expr : eq-expr | and-expr '&&' eq-expr."
449 (let ((result (hif-eq-expr)))
450 (while (eq hif-token
'and
)
452 (setq result
(list 'hif-and result
(hif-eq-expr))))
455 (defun hif-eq-expr ()
456 "Parse an eq-expr : math | eq-expr `=='|`!='|`<'|`>'|`>='|`<=' math."
457 (let ((result (hif-math))
459 (while (memq hif-token
'(equal hif-notequal hif-greater hif-less
460 hif-greater-equal hif-less-equal
))
461 (setq eq-token hif-token
)
463 (setq result
(list eq-token result
(hif-math))))
467 "Parse an expression with + or - and simpler things.
468 math : factor | math '+|-' factor."
469 (let ((result (hif-factor))
471 (while (memq hif-token
'(hif-plus hif-minus hif-logior hif-logand
))
472 (setq math-op hif-token
)
474 (setq result
(list math-op result
(hif-factor))))
478 "Parse a factor: '!' factor | '(' expr ')' | 'defined(' id ')' | id."
482 (list 'hif-not
(hif-factor)))
484 ((eq hif-token
'lparen
)
486 (let ((result (hif-expr)))
487 (if (not (eq hif-token
'rparen
))
488 (error "Bad token in parenthesized expression: %s" hif-token
)
492 ((eq hif-token
'hif-defined
)
494 (let ((paren (when (eq hif-token
'lparen
) (hif-nexttoken) t
))
496 (if (memq hif-token
'(or and not hif-defined lparen rparen
))
497 (error "Error: unexpected token: %s" hif-token
))
500 (unless (eq hif-token
'rparen
)
501 (error "Error: expected \")\" after identifier")))
503 `(hif-defined (quote ,ident
))))
506 (prog1 hif-token
(hif-nexttoken)))
509 ((memq hif-token
'(hif-minus hif-plus
))
510 (list (prog1 hif-token
(hif-nexttoken)) 0 (hif-factor)))
513 (let ((ident hif-token
))
514 (if (memq ident
'(or and
))
515 (error "Error: missing identifier"))
517 `(hif-lookup (quote ,ident
))))))
519 (defun hif-mathify (val)
520 "Treat VAL as a number: if it's t or nil, use 1 or 0."
525 (defun hif-conditional (a b c
)
526 (if (not (zerop (hif-mathify a
))) (hif-mathify b
) (hif-mathify c
)))
528 (and (not (zerop (hif-mathify a
))) (not (zerop (hif-mathify b
)))))
530 (or (not (zerop (hif-mathify a
))) (not (zerop (hif-mathify b
)))))
532 (zerop (hif-mathify a
)))
534 (defmacro hif-mathify-binop
(fun)
536 ,(format "Like `%s' but treat t and nil as 1 and 0." fun
)
537 (,fun
(hif-mathify a
) (hif-mathify b
))))
539 (defalias 'hif-plus
(hif-mathify-binop +))
540 (defalias 'hif-minus
(hif-mathify-binop -
))
541 (defalias 'hif-notequal
(hif-mathify-binop /=))
542 (defalias 'hif-greater
(hif-mathify-binop >))
543 (defalias 'hif-less
(hif-mathify-binop <))
544 (defalias 'hif-greater-equal
(hif-mathify-binop >=))
545 (defalias 'hif-less-equal
(hif-mathify-binop <=))
546 (defalias 'hif-logior
(hif-mathify-binop logior
))
547 (defalias 'hif-logand
(hif-mathify-binop logand
))
549 ;;;----------- end of parser -----------------------
552 (defun hif-canonicalize ()
553 "When at beginning of #ifX, return a Lisp expression for its condition."
555 (let ((negate (looking-at hif-ifndef-regexp
)))
556 (re-search-forward hif-ifx-regexp
)
557 (let* ((tokens (hif-tokenize (point)
558 (progn (hif-end-of-line) (point))))
559 (expr (hif-parse-if-exp tokens
)))
560 ;; (message "hif-canonicalized: %s" expr)
566 (defun hif-find-any-ifX ()
567 "Move to next #if..., or #ifndef, at point or after."
568 ;; (message "find ifX at %d" (point))
570 (re-search-forward hif-ifx-regexp
(point-max) t
)
571 (beginning-of-line)))
574 (defun hif-find-next-relevant ()
575 "Move to next #if..., #else, or #endif, after the current line."
576 ;; (message "hif-find-next-relevant at %d" (point))
578 ;; avoid infinite recursion by only going to beginning of line if match found
579 (if (re-search-forward hif-ifx-else-endif-regexp
(point-max) t
)
580 (beginning-of-line)))
582 (defun hif-find-previous-relevant ()
583 "Move to previous #if..., #else, or #endif, before the current line."
584 ;; (message "hif-find-previous-relevant at %d" (point))
586 ;; avoid infinite recursion by only going to beginning of line if match found
587 (if (re-search-backward hif-ifx-else-endif-regexp
(point-min) t
)
588 (beginning-of-line)))
591 (defun hif-looking-at-ifX () ;; Should eventually see #if
592 (looking-at hif-ifx-regexp
))
593 (defun hif-looking-at-endif ()
594 (looking-at hif-endif-regexp
))
595 (defun hif-looking-at-else ()
596 (looking-at hif-else-regexp
))
600 (defun hif-ifdef-to-endif ()
601 "If positioned at #ifX or #else form, skip to corresponding #endif."
602 ;; (message "hif-ifdef-to-endif at %d" (point)) (sit-for 1)
603 (hif-find-next-relevant)
604 (cond ((hif-looking-at-ifX)
605 (hif-ifdef-to-endif) ; find endif of nested if
606 (hif-ifdef-to-endif)) ; find outer endif or else
607 ((hif-looking-at-else)
608 (hif-ifdef-to-endif)) ; find endif following else
609 ((hif-looking-at-endif)
612 (error "Mismatched #ifdef #endif pair"))))
615 (defun hif-endif-to-ifdef ()
616 "If positioned at #endif form, skip backward to corresponding #ifX."
617 ;; (message "hif-endif-to-ifdef at %d" (point))
618 (let ((start (point)))
619 (hif-find-previous-relevant)
620 (if (= start
(point))
621 (error "Mismatched #ifdef #endif pair")))
622 (cond ((hif-looking-at-endif)
623 (hif-endif-to-ifdef) ; find beginning of nested if
624 (hif-endif-to-ifdef)) ; find beginning of outer if or else
625 ((hif-looking-at-else)
626 (hif-endif-to-ifdef))
627 ((hif-looking-at-ifX)
629 (t))) ; never gets here
632 (defun forward-ifdef (&optional arg
)
633 "Move point to beginning of line of the next ifdef-endif.
634 With argument, do this that many times."
636 (or arg
(setq arg
1))
637 (if (< arg
0) (backward-ifdef (- arg
))
640 (let ((start (point)))
641 (unless (hif-looking-at-ifX)
642 (hif-find-next-relevant))
643 (if (hif-looking-at-ifX)
646 (error "No following #ifdef"))))))
649 (defun backward-ifdef (&optional arg
)
650 "Move point to beginning of the previous ifdef-endif.
651 With argument, do this that many times."
653 (or arg
(setq arg
1))
654 (if (< arg
0) (forward-ifdef (- arg
))
658 (let ((start (point)))
659 (unless (hif-looking-at-endif)
660 (hif-find-previous-relevant))
661 (if (hif-looking-at-endif)
664 (error "No previous #ifdef"))))))
668 "Move point to beginning of nested ifdef or else-part."
670 (let ((start (point)))
671 (hif-find-next-relevant)
672 (if (or (hif-looking-at-ifX) (hif-looking-at-else))
675 (error "No following #ifdef"))))
679 "Move point to beginning of enclosing ifdef or else-part."
682 (let ((start (point)))
683 (unless (hif-looking-at-endif)
684 (hif-find-previous-relevant))
685 (if (hif-looking-at-endif)
686 (hif-endif-to-ifdef))
687 (if (= start
(point))
688 (error "No previous #ifdef"))))
690 (defun next-ifdef (&optional arg
)
691 "Move to the beginning of the next #ifX, #else, or #endif.
692 With argument, do this that many times."
694 (or arg
(setq arg
1))
695 (if (< arg
0) (previous-ifdef (- arg
))
698 (hif-find-next-relevant)
701 (error "No following #ifdefs, #elses, or #endifs")))))
703 (defun previous-ifdef (&optional arg
)
704 "Move to the beginning of the previous #ifX, #else, or #endif.
705 With argument, do this that many times."
707 (or arg
(setq arg
1))
708 (if (< arg
0) (next-ifdef (- arg
))
711 (let ((start (point)))
712 (hif-find-previous-relevant)
713 (if (= start
(point))
714 (error "No previous #ifdefs, #elses, or #endifs"))))))
717 ;;===%%SF%% parsing (End) ===
720 ;;===%%SF%% hide-ifdef-hiding (Start) ===
723 ;;; A range is a structure with four components:
724 ;;; ELSE-P True if there was an else clause for the ifdef.
725 ;;; START The start of the range. (beginning of line)
726 ;;; ELSE The else marker (beginning of line)
727 ;;; Only valid if ELSE-P is true.
728 ;;; END The end of the range. (beginning of line)
730 (defsubst hif-make-range
(start end
&optional else
)
731 (list start else end
))
733 (defsubst hif-range-start
(range) (elt range
0))
734 (defsubst hif-range-else
(range) (elt range
1))
735 (defsubst hif-range-end
(range) (elt range
2))
740 ;;; The workhorse, it delimits the #if region. Reasonably simple:
741 ;;; Skip until an #else or #endif is found, remembering positions. If
742 ;;; an #else was found, skip some more, looking for the true #endif.
744 (defun hif-find-range ()
745 "Return a Range structure describing the current #if region.
746 Point is left unchanged."
747 ;; (message "hif-find-range at %d" (point))
750 (let ((start (point))
753 ;; Part one. Look for either #endif or #else.
754 ;; This loop-and-a-half dedicated to E. Dijkstra.
756 (hif-find-next-relevant)
757 (hif-looking-at-ifX)) ; Skip nested ifdef
758 (hif-ifdef-to-endif))
759 ;; Found either a #else or an #endif.
760 (cond ((hif-looking-at-else)
763 (setq end
(point)))) ; (line-end-position)
764 ;; If found #else, look for #endif.
767 (hif-find-next-relevant)
768 (hif-looking-at-ifX)) ; Skip nested ifdef
769 (hif-ifdef-to-endif))
770 (if (hif-looking-at-else)
771 (error "Found two elses in a row? Broken!"))
772 (setq end
(point))) ; (line-end-position)
773 (hif-make-range start end else
))))
778 (defun hif-hide-line (point)
779 "Hide the line containing point. Does nothing if `hide-ifdef-lines' is nil."
780 (when hide-ifdef-lines
783 (hide-ifdef-region-internal
784 (line-beginning-position) (progn (hif-end-of-line) (point))))))
787 ;;; Hif-Possibly-Hide
788 ;;; There are four cases. The #ifX expression is "taken" if it
789 ;;; the hide-ifdef-evaluator returns T. Presumably, this means the code
790 ;;; inside the #ifdef would be included when the program was
793 ;;; Case 1: #ifX taken, and there's an #else.
794 ;;; The #else part must be hidden. The #if (then) part must be
795 ;;; processed for nested #ifX's.
796 ;;; Case 2: #ifX taken, and there's no #else.
797 ;;; The #if part must be processed for nested #ifX's.
798 ;;; Case 3: #ifX not taken, and there's an #else.
799 ;;; The #if part must be hidden. The #else part must be processed
801 ;;; Case 4: #ifX not taken, and there's no #else.
802 ;;; The #ifX part must be hidden.
804 ;;; Further processing is done by narrowing to the relevant region
805 ;;; and just recursively calling hide-ifdef-guts.
807 ;;; When hif-possibly-hide returns, point is at the end of the
808 ;;; possibly-hidden range.
810 (defun hif-recurse-on (start end
)
811 "Call `hide-ifdef-guts' after narrowing to end of START line and END line."
816 (narrow-to-region (point) end
)
819 (defun hif-possibly-hide ()
820 "Called at #ifX expression, this hides those parts that should be hidden.
821 It uses the judgement of `hide-ifdef-evaluator'."
822 ;; (message "hif-possibly-hide") (sit-for 1)
823 (let ((test (hif-canonicalize))
824 (range (hif-find-range)))
825 ;; (message "test = %s" test) (sit-for 1)
827 (hif-hide-line (hif-range-end range
))
828 (if (not (hif-not (funcall hide-ifdef-evaluator test
)))
829 (cond ((hif-range-else range
) ; case 1
830 (hif-hide-line (hif-range-else range
))
831 (hide-ifdef-region (hif-range-else range
)
832 (1- (hif-range-end range
)))
833 (hif-recurse-on (hif-range-start range
)
834 (hif-range-else range
)))
836 (hif-recurse-on (hif-range-start range
)
837 (hif-range-end range
))))
838 (cond ((hif-range-else range
) ; case 3
839 (hif-hide-line (hif-range-else range
))
840 (hide-ifdef-region (hif-range-start range
)
841 (1- (hif-range-else range
)))
842 (hif-recurse-on (hif-range-else range
)
843 (hif-range-end range
)))
845 (hide-ifdef-region (point)
846 (1- (hif-range-end range
))))))
847 (hif-hide-line (hif-range-start range
)) ; Always hide start.
848 (goto-char (hif-range-end range
))
853 (defun hide-ifdef-guts ()
854 "Does most of the work of `hide-ifdefs'.
855 It does not do the work that's pointless to redo on a recursive entry."
856 ;; (message "hide-ifdef-guts")
858 (goto-char (point-min))
859 (while (hif-find-any-ifX)
860 (hif-possibly-hide))))
862 ;;===%%SF%% hide-ifdef-hiding (End) ===
865 ;;===%%SF%% exports (Start) ===
867 (defun hide-ifdef-toggle-read-only ()
868 "Toggle `hide-ifdef-read-only'."
870 (setq hide-ifdef-read-only
(not hide-ifdef-read-only
))
871 (message "Hide-Read-Only %s"
872 (if hide-ifdef-read-only
"ON" "OFF"))
873 (if hide-ifdef-hiding
874 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
)))
875 (force-mode-line-update))
877 (defun hide-ifdef-toggle-outside-read-only ()
878 "Replacement for `toggle-read-only' within Hide-Ifdef mode."
880 (setq hif-outside-read-only
(not hif-outside-read-only
))
881 (message "Read only %s"
882 (if hif-outside-read-only
"ON" "OFF"))
883 (setq buffer-read-only
884 (or (and hide-ifdef-hiding hide-ifdef-read-only
)
885 hif-outside-read-only
))
886 (force-mode-line-update))
888 (defun hide-ifdef-toggle-shadowing ()
891 (set (make-local-variable 'hide-ifdef-shadow
) (not hide-ifdef-shadow
))
892 (message "Shadowing %s" (if hide-ifdef-shadow
"ON" "OFF"))
895 (dolist (overlay (overlays-in (point-min) (point-max)))
896 (when (overlay-get overlay
'hide-ifdef
)
897 (if hide-ifdef-shadow
899 (overlay-put overlay
'invisible nil
)
900 (overlay-put overlay
'face
'hide-ifdef-shadow
))
901 (overlay-put overlay
'face nil
)
902 (overlay-put overlay
'invisible
'hide-ifdef
))))))
904 (defun hide-ifdef-define (var)
905 "Define a VAR so that #ifdef VAR would be included."
906 (interactive "SDefine what? ")
908 (if hide-ifdef-hiding
(hide-ifdefs)))
910 (defun hide-ifdef-undef (var)
911 "Undefine a VAR so that #ifdef VAR would not be included."
912 (interactive "SUndefine what? ")
913 (hif-set-var var nil
)
914 (if hide-ifdef-hiding
(hide-ifdefs)))
917 (defun hide-ifdefs (&optional nomsg
)
918 "Hide the contents of some #ifdefs.
919 Assume that defined symbols have been added to `hide-ifdef-env'.
920 The text hidden is the text that would not be included by the C
921 preprocessor if it were given the file with those symbols defined.
923 Turn off hiding by calling `show-ifdefs'."
926 (message "Hiding...")
927 (setq hif-outside-read-only buffer-read-only
)
928 (unless hide-ifdef-mode
(hide-ifdef-mode 1)) ; turn on hide-ifdef-mode
929 (if hide-ifdef-hiding
930 (show-ifdefs)) ; Otherwise, deep confusion.
931 (setq hide-ifdef-hiding t
)
933 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
))
935 (message "Hiding done")))
938 (defun show-ifdefs ()
939 "Cancel the effects of `hide-ifdef': show the contents of all #ifdefs."
941 (setq buffer-read-only hif-outside-read-only
)
943 (setq hide-ifdef-hiding nil
))
946 (defun hif-find-ifdef-block ()
947 "Utility for hide and show `ifdef-block'.
948 Return as (TOP . BOTTOM) the extent of ifdef block."
950 (cons (save-excursion
952 (unless (or (hif-looking-at-else) (hif-looking-at-ifX))
956 (setq max-bottom
(1- (point)))))
959 (unless (hif-looking-at-endif)
960 (hif-find-next-relevant))
961 (while (hif-looking-at-ifX)
963 (hif-find-next-relevant))
964 (min max-bottom
(1- (point)))))))
967 (defun hide-ifdef-block ()
968 "Hide the ifdef block (true or false part) enclosing or before the cursor."
970 (unless hide-ifdef-mode
(hide-ifdef-mode 1))
971 (let ((top-bottom (hif-find-ifdef-block)))
972 (hide-ifdef-region (car top-bottom
) (cdr top-bottom
))
973 (when hide-ifdef-lines
974 (hif-hide-line (car top-bottom
))
975 (hif-hide-line (1+ (cdr top-bottom
))))
976 (setq hide-ifdef-hiding t
))
977 (setq buffer-read-only
(or hide-ifdef-read-only hif-outside-read-only
)))
979 (defun show-ifdef-block ()
980 "Show the ifdef block (true or false part) enclosing or before the cursor."
982 (let ((top-bottom (hif-find-ifdef-block)))
984 (hif-show-ifdef-region
986 (goto-char (car top-bottom
)) (line-beginning-position))
988 (goto-char (1+ (cdr top-bottom
)))
989 (hif-end-of-line) (point)))
990 (hif-show-ifdef-region (1- (car top-bottom
)) (cdr top-bottom
)))))
993 ;;; definition alist support
995 (defvar hide-ifdef-define-alist nil
996 "A global assoc list of pre-defined symbol lists.")
998 (defun hif-compress-define-list (env)
999 "Compress the define list ENV into a list of defined symbols only."
1000 (let ((new-defs nil
))
1001 (dolist (def env new-defs
)
1002 (if (hif-lookup (car def
)) (push (car env
) new-defs
)))))
1004 (defun hide-ifdef-set-define-alist (name)
1005 "Set the association for NAME to `hide-ifdef-env'."
1006 (interactive "SSet define list: ")
1007 (push (cons name
(hif-compress-define-list hide-ifdef-env
))
1008 hide-ifdef-define-alist
))
1010 (defun hide-ifdef-use-define-alist (name)
1011 "Set `hide-ifdef-env' to the define list specified by NAME."
1013 (list (completing-read "Use define list: "
1014 (mapcar (lambda (x) (symbol-name (car x
)))
1015 hide-ifdef-define-alist
)
1017 (if (stringp name
) (setq name
(intern name
)))
1018 (let ((define-list (assoc name hide-ifdef-define-alist
)))
1020 (setq hide-ifdef-env
1021 (mapcar (lambda (arg) (cons arg t
))
1023 (error "No define list for %s" name
))
1024 (if hide-ifdef-hiding
(hide-ifdefs))))
1028 ;;; hideif.el ends here