1;;; hideif.el --- hides selected code within ifdef 2 3;; Copyright (C) 1988, 1994, 2001, 2002, 2003, 2004, 2005, 2006, 2007 4;; Free Software Foundation, Inc. 5 6;; Author: Daniel LaLiberte <liberte@holonexus.org> 7;; Maintainer: FSF 8;; Keywords: c, outlines 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;; To initialize, toggle the hide-ifdef minor mode with 30;; 31;; M-x hide-ifdef-mode 32;; 33;; This will set up key bindings and call hide-ifdef-mode-hook if it 34;; has a value. To explicitly hide ifdefs using a buffer-local 35;; define list (default empty), type 36;; 37;; M-x hide-ifdefs or C-c @ h 38;; 39;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't 40;; pass through. The support of constant expressions in #if lines is 41;; limited to identifiers, parens, and the operators: &&, ||, !, and 42;; "defined". Please extend this. 43;; 44;; The hidden code is marked by ellipses (...). Be 45;; cautious when editing near ellipses, since the hidden text is 46;; still in the buffer, and you can move the point into it and modify 47;; text unawares. 48;; You can make your buffer read-only while hide-ifdef-hiding by setting 49;; hide-ifdef-read-only to a non-nil value. You can toggle this 50;; variable with hide-ifdef-toggle-read-only (C-c @ C-q). 51;; 52;; You can undo the effect of hide-ifdefs by typing 53;; 54;; M-x show-ifdefs or C-c @ s 55;; 56;; Use M-x hide-ifdef-define (C-c @ d) to define a symbol. 57;; Use M-x hide-ifdef-undef (C-c @ u) to undefine a symbol. 58;; 59;; If you define or undefine a symbol while hide-ifdef-mode is in effect, 60;; the display will be updated. Only the define list for the current 61;; buffer will be affected. You can save changes to the local define 62;; list with hide-ifdef-set-define-alist. This adds entries 63;; to hide-ifdef-define-alist. 64;; 65;; If you have defined a hide-ifdef-mode-hook, you can set 66;; up a list of symbols that may be used by hide-ifdefs as in the 67;; following example: 68;; 69;; (add-hook 'hide-ifdef-mode-hook 70;; (lambda () 71;; (unless hide-ifdef-define-alist 72;; (setq hide-ifdef-define-alist 73;; '((list1 ONE TWO) 74;; (list2 TWO THREE)))) 75;; (hide-ifdef-use-define-alist 'list2))) ; use list2 by default 76;; 77;; You can call hide-ifdef-use-define-alist (C-c @ U) at any time to specify 78;; another list to use. 79;; 80;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called, 81;; set hide-ifdef-initially to non-nil. 82;; 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 88;; better. 89;; 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. 92;; 93;; You can move the point between ifdefs with forward-ifdef, backward-ifdef, 94;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef. 95;; 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). 99;; 100;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL. 101;; Extensively modified by Daniel LaLiberte (while at Gould). 102;; 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. 108 109;;; Code: 110 111(require 'cc-mode) 112 113(defgroup hide-ifdef nil 114 "Hide selected code within `ifdef'." 115 :group 'c) 116 117(defvar hide-ifdef-mode-submap 118 ;; Set up the submap that goes after the prefix key. 119 (let ((map (make-sparse-keymap))) 120 (define-key map "d" 'hide-ifdef-define) 121 (define-key map "u" 'hide-ifdef-undef) 122 (define-key map "D" 'hide-ifdef-set-define-alist) 123 (define-key map "U" 'hide-ifdef-use-define-alist) 124 125 (define-key map "h" 'hide-ifdefs) 126 (define-key map "s" 'show-ifdefs) 127 (define-key map "\C-d" 'hide-ifdef-block) 128 (define-key map "\C-s" 'show-ifdef-block) 129 130 (define-key map "\C-q" 'hide-ifdef-toggle-read-only) 131 (substitute-key-definition 132 'toggle-read-only 'hide-ifdef-toggle-outside-read-only map) 133 map) 134 "Keymap used by `hide-ifdef-mode' under `hide-ifdef-mode-prefix-key'.") 135 136(defconst hide-ifdef-mode-prefix-key "\C-c@" 137 "Prefix key for all Hide-Ifdef mode commands.") 138 139(defvar hide-ifdef-mode-map 140 ;; Set up the mode's main map, which leads via the prefix key to the submap. 141 (let ((map (make-sparse-keymap))) 142 (define-key map hide-ifdef-mode-prefix-key hide-ifdef-mode-submap) 143 map) 144 "Keymap used with `hide-ifdef-mode'.") 145 146(defvar hide-ifdef-hiding nil 147 "Non-nil when text may be hidden.") 148 149(or (assq 'hide-ifdef-hiding minor-mode-alist) 150 (setq minor-mode-alist 151 (cons '(hide-ifdef-hiding " Hiding") 152 minor-mode-alist))) 153 154;; fix c-mode syntax table so we can recognize whole symbols. 155(defvar hide-ifdef-syntax-table 156 (let ((st (copy-syntax-table c-mode-syntax-table))) 157 (modify-syntax-entry ?_ "w" st) 158 (modify-syntax-entry ?& "." st) 159 (modify-syntax-entry ?\| "." st) 160 st) 161 "Syntax table used for tokenizing #if expressions.") 162 163(defvar hide-ifdef-env nil 164 "An alist of defined symbols and their values.") 165 166(defvar hif-outside-read-only nil 167 "Internal variable. Saves the value of `buffer-read-only' while hiding.") 168 169;;;###autoload 170(define-minor-mode hide-ifdef-mode 171 "Toggle Hide-Ifdef mode. This is a minor mode, albeit a large one. 172With ARG, turn Hide-Ifdef mode on if arg is positive, off otherwise. 173In Hide-Ifdef mode, code within #ifdef constructs that the C preprocessor 174would eliminate may be hidden from view. Several variables affect 175how the hiding is done: 176 177`hide-ifdef-env' 178 An association list of defined and undefined symbols for the 179 current buffer. Initially, the global value of `hide-ifdef-env' 180 is used. 181 182`hide-ifdef-define-alist' 183 An association list of defined symbol lists. 184 Use `hide-ifdef-set-define-alist' to save the current `hide-ifdef-env' 185 and `hide-ifdef-use-define-alist' to set the current `hide-ifdef-env' 186 from one of the lists in `hide-ifdef-define-alist'. 187 188`hide-ifdef-lines' 189 Set to non-nil to not show #if, #ifdef, #ifndef, #else, and 190 #endif lines when hiding. 191 192`hide-ifdef-initially' 193 Indicates whether `hide-ifdefs' should be called when Hide-Ifdef mode 194 is activated. 195 196`hide-ifdef-read-only' 197 Set to non-nil if you want to make buffers read only while hiding. 198 After `show-ifdefs', read-only status is restored to previous value. 199 200\\{hide-ifdef-mode-map}" 201 :group 'hide-ifdef :lighter " Ifdef" 202 (if hide-ifdef-mode 203 (progn 204 ;; inherit global values 205 (set (make-local-variable 'hide-ifdef-env) 206 (default-value 'hide-ifdef-env)) 207 (set (make-local-variable 'hide-ifdef-hiding) 208 (default-value 'hide-ifdef-hiding)) 209 (set (make-local-variable 'hif-outside-read-only) buffer-read-only) 210 (set (make-local-variable 'line-move-ignore-invisible) t) 211 (add-hook 'change-major-mode-hook 212 (lambda () (hide-ifdef-mode -1)) nil t) 213 214 (add-to-invisibility-spec '(hide-ifdef . t)) 215 216 (if hide-ifdef-initially 217 (hide-ifdefs) 218 (show-ifdefs))) 219 ;; else end hide-ifdef-mode 220 (kill-local-variable 'line-move-ignore-invisible) 221 (remove-from-invisibility-spec '(hide-ifdef . t)) 222 (if hide-ifdef-hiding 223 (show-ifdefs)))) 224 225 226(defun hif-show-all () 227 "Show all of the text in the current buffer." 228 (interactive) 229 (hif-show-ifdef-region (point-min) (point-max))) 230 231;; By putting this on after-revert-hook, we arrange that it only 232;; does anything when revert-buffer avoids turning off the mode. 233;; (That can happen in VC.) 234(defun hif-after-revert-function () 235 (and hide-ifdef-mode hide-ifdef-hiding 236 (hide-ifdefs t))) 237(add-hook 'after-revert-hook 'hif-after-revert-function) 238 239(defun hif-end-of-line () 240 (end-of-line) 241 (while (= (logand 1 (skip-chars-backward "\\\\")) 1) 242 (end-of-line 2))) 243 244(defun hide-ifdef-region-internal (start end) 245 (remove-overlays start end 'invisible 'hide-ifdef) 246 (let ((o (make-overlay start end))) 247 (overlay-put o 'invisible 'hide-ifdef))) 248 249(defun hide-ifdef-region (start end) 250 "START is the start of a #if or #else form. END is the ending part. 251Everything including these lines is made invisible." 252 (save-excursion 253 (goto-char start) (hif-end-of-line) (setq start (point)) 254 (goto-char end) (hif-end-of-line) (setq end (point)) 255 (hide-ifdef-region-internal start end))) 256 257(defun hif-show-ifdef-region (start end) 258 "Everything between START and END is made visible." 259 (remove-overlays start end 'invisible 'hide-ifdef)) 260 261 262;;===%%SF%% evaluation (Start) === 263 264;; It is not useful to set this to anything but `eval'. 265;; In fact, the variable might as well be eliminated. 266(defvar hide-ifdef-evaluator 'eval 267 "The function to use to evaluate a form. 268The evaluator is given a canonical form and returns t if text under 269that form should be displayed.") 270 271(defvar hif-undefined-symbol nil 272 "...is by default considered to be false.") 273 274 275(defun hif-set-var (var value) 276 "Prepend (var value) pair to hide-ifdef-env." 277 (setq hide-ifdef-env (cons (cons var value) hide-ifdef-env))) 278 279 280(defun hif-lookup (var) 281 ;; (message "hif-lookup %s" var) 282 (let ((val (assoc var hide-ifdef-env))) 283 (if val 284 (cdr val) 285 hif-undefined-symbol))) 286 287(defun hif-defined (var) 288 (if (assoc var hide-ifdef-env) 1 0)) 289 290;;===%%SF%% evaluation (End) === 291 292 293 294;;===%%SF%% parsing (Start) === 295;;; The code that understands what ifs and ifdef in files look like. 296 297(defconst hif-cpp-prefix "\\(^\\|\r\\)[ \t]*#[ \t]*") 298(defconst hif-ifndef-regexp (concat hif-cpp-prefix "ifndef")) 299(defconst hif-ifx-regexp (concat hif-cpp-prefix "if\\(n?def\\)?[ \t]+")) 300(defconst hif-else-regexp (concat hif-cpp-prefix "else")) 301(defconst hif-endif-regexp (concat hif-cpp-prefix "endif")) 302(defconst hif-ifx-else-endif-regexp 303 (concat hif-ifx-regexp "\\|" hif-else-regexp "\\|" hif-endif-regexp)) 304 305;; Used to store the current token and the whole token list during parsing. 306;; Only bound dynamically. 307(defvar hif-token) 308(defvar hif-token-list) 309 310;; pattern to match initial identifier, !, &&, ||, (, or ). 311;; Added ==, + and -: garyo@avs.com 8/9/94 312(defconst hif-token-regexp 313 "\\(&&\\|||\\|[!=]=\\|!\\|[()+?:-]\\|[<>]=?\\|\\w+\\)") 314 315(defun hif-tokenize (start end) 316 "Separate string between START and END into a list of tokens." 317 (let ((token-list nil)) 318 (with-syntax-table hide-ifdef-syntax-table 319 (save-excursion 320 (goto-char start) 321 (while (progn (forward-comment (point-max)) (< (point) end)) 322 ;; (message "expr-start = %d" expr-start) (sit-for 1) 323 (cond 324 ((looking-at "\\\\\n") 325 (forward-char 2)) 326 327 ((looking-at hif-token-regexp) 328 (let ((token (buffer-substring (point) (match-end 0)))) 329 (goto-char (match-end 0)) 330 ;; (message "token: %s" token) (sit-for 1) 331 (push (cond 332 ((string-equal token "||") 'or) 333 ((string-equal token "&&") 'and) 334 ((string-equal token "==") 'equal) 335 ((string-equal token "!=") 'hif-notequal) 336 ((string-equal token "!") 'not) 337 ((string-equal token "defined") 'hif-defined) 338 ((string-equal token "(") 'lparen) 339 ((string-equal token ")") 'rparen) 340 ((string-equal token ">") 'hif-greater) 341 ((string-equal token "<") 'hif-less) 342 ((string-equal token ">=") 'hif-greater-equal) 343 ((string-equal token "<=") 'hif-less-equal) 344 ((string-equal token "+") 'hif-plus) 345 ((string-equal token "-") 'hif-minus) 346 ((string-equal token "?") 'hif-conditional) 347 ((string-equal token ":") 'hif-colon) 348 ((string-match "\\`[0-9]*\\'" token) 349 (string-to-number token)) 350 (t (intern token))) 351 token-list))) 352 (t (error "Bad #if expression: %s" (buffer-string))))))) 353 (nreverse token-list))) 354 355;;;----------------------------------------------------------------- 356;;; Translate C preprocessor #if expressions using recursive descent. 357;;; This parser is limited to the operators &&, ||, !, and "defined". 358;;; Added ==, !=, +, and -. Gary Oberbrunner, garyo@avs.com, 8/9/94 359 360(defsubst hif-nexttoken () 361 "Pop the next token from token-list into the let variable \"hif-token\"." 362 (setq hif-token (pop hif-token-list))) 363 364(defun hif-parse-if-exp (hif-token-list) 365 "Parse the TOKEN-LIST. Return translated list in prefix form." 366 (hif-nexttoken) 367 (prog1 368 (hif-expr) 369 (if hif-token ; is there still a token? 370 (error "Error: unexpected token: %s" hif-token)))) 371 372(defun hif-expr () 373 "Parse an expression as found in #if. 374 expr : or-expr | or-expr '?' expr ':' expr." 375 (let ((result (hif-or-expr)) 376 middle) 377 (while (eq hif-token 'hif-conditional) 378 (hif-nexttoken) 379 (setq middle (hif-expr)) 380 (if (eq hif-token 'hif-colon) 381 (progn 382 (hif-nexttoken) 383 (setq result (list 'hif-conditional result middle (hif-expr)))) 384 (error "Error: unexpected token: %s" hif-token))) 385 result)) 386 387(defun hif-or-expr () 388 "Parse n or-expr : and-expr | or-expr '||' and-expr." 389 (let ((result (hif-and-expr))) 390 (while (eq hif-token 'or) 391 (hif-nexttoken) 392 (setq result (list 'hif-or result (hif-and-expr)))) 393 result)) 394 395(defun hif-and-expr () 396 "Parse an and-expr : eq-expr | and-expr '&&' eq-expr." 397 (let ((result (hif-eq-expr))) 398 (while (eq hif-token 'and) 399 (hif-nexttoken) 400 (setq result (list 'hif-and result (hif-eq-expr)))) 401 result)) 402 403(defun hif-eq-expr () 404 "Parse an eq-expr : math | eq-expr `=='|`!='|`<'|`>'|`>='|`<=' math." 405 (let ((result (hif-math)) 406 (eq-token nil)) 407 (while (memq hif-token '(equal hif-notequal hif-greater hif-less 408 hif-greater-equal hif-less-equal)) 409 (setq eq-token hif-token) 410 (hif-nexttoken) 411 (setq result (list eq-token result (hif-math)))) 412 result)) 413 414(defun hif-math () 415 "Parse an expression with + or - and simpler things. 416 math : factor | math '+|-' factor." 417 (let ((result (hif-factor)) 418 (math-op nil)) 419 (while (memq hif-token '(hif-plus hif-minus)) 420 (setq math-op hif-token) 421 (hif-nexttoken) 422 (setq result (list math-op result (hif-factor)))) 423 result)) 424 425(defun hif-factor () 426 "Parse a factor: '!' factor | '(' expr ')' | 'defined(' id ')' | id." 427 (cond 428 ((eq hif-token 'not) 429 (hif-nexttoken) 430 (list 'hif-not (hif-factor))) 431 432 ((eq hif-token 'lparen) 433 (hif-nexttoken) 434 (let ((result (hif-expr))) 435 (if (not (eq hif-token 'rparen)) 436 (error "Bad token in parenthesized expression: %s" hif-token) 437 (hif-nexttoken) 438 result))) 439 440 ((eq hif-token 'hif-defined) 441 (hif-nexttoken) 442 (let ((paren (when (eq hif-token 'lparen) (hif-nexttoken) t)) 443 (ident hif-token)) 444 (if (memq hif-token '(or and not hif-defined lparen rparen)) 445 (error "Error: unexpected token: %s" hif-token)) 446 (when paren 447 (hif-nexttoken) 448 (unless (eq hif-token 'rparen) 449 (error "Error: expected \")\" after identifier"))) 450 (hif-nexttoken) 451 `(hif-defined (quote ,ident)))) 452 453 ((numberp hif-token) 454 (prog1 hif-token (hif-nexttoken))) 455 456 (t ; identifier 457 (let ((ident hif-token)) 458 (if (memq ident '(or and)) 459 (error "Error: missing identifier")) 460 (hif-nexttoken) 461 `(hif-lookup (quote ,ident)))))) 462 463(defun hif-mathify (val) 464 "Treat VAL as a number: if it's t or nil, use 1 or 0." 465 (cond ((eq val t) 1) 466 ((null val) 0) 467 (t val))) 468 469(defun hif-conditional (a b c) 470 (if (not (zerop (hif-mathify a))) (hif-mathify b) (hif-mathify c))) 471(defun hif-and (a b) 472 (and (not (zerop (hif-mathify a))) (not (zerop (hif-mathify b))))) 473(defun hif-or (a b) 474 (or (not (zerop (hif-mathify a))) (not (zerop (hif-mathify b))))) 475(defun hif-not (a) 476 (zerop (hif-mathify a))) 477(defun hif-plus (a b) 478 "Like ordinary plus but treat t and nil as 1 and 0." 479 (+ (hif-mathify a) (hif-mathify b))) 480(defun hif-minus (a b) 481 "Like ordinary minus but treat t and nil as 1 and 0." 482 (- (hif-mathify a) (hif-mathify b))) 483(defun hif-notequal (a b) 484 "Like (not (equal A B)) but as one symbol." 485 (not (equal a b))) 486(defun hif-greater (a b) 487 "Simple comparison." 488 (> (hif-mathify a) (hif-mathify b))) 489(defun hif-less (a b) 490 "Simple comparison." 491 (< (hif-mathify a) (hif-mathify b))) 492(defun hif-greater-equal (a b) 493 "Simple comparison." 494 (>= (hif-mathify a) (hif-mathify b))) 495(defun hif-less-equal (a b) 496 "Simple comparison." 497 (<= (hif-mathify a) (hif-mathify b))) 498;;;----------- end of parser ----------------------- 499 500 501(defun hif-canonicalize () 502 "When at beginning of #ifX, return a Lisp expression for its condition." 503 (save-excursion 504 (let ((negate (looking-at hif-ifndef-regexp))) 505 (re-search-forward hif-ifx-regexp) 506 (let* ((tokens (hif-tokenize (point) 507 (progn (hif-end-of-line) (point)))) 508 (expr (hif-parse-if-exp tokens))) 509 ;; (message "hif-canonicalized: %s" expr) 510 (if negate 511 (list 'hif-not expr) 512 expr))))) 513 514 515(defun hif-find-any-ifX () 516 "Move to next #if..., or #ifndef, at point or after." 517 ;; (message "find ifX at %d" (point)) 518 (prog1 519 (re-search-forward hif-ifx-regexp (point-max) t) 520 (beginning-of-line))) 521 522 523(defun hif-find-next-relevant () 524 "Move to next #if..., #else, or #endif, after the current line." 525 ;; (message "hif-find-next-relevant at %d" (point)) 526 (end-of-line) 527 ;; avoid infinite recursion by only going to beginning of line if match found 528 (if (re-search-forward hif-ifx-else-endif-regexp (point-max) t) 529 (beginning-of-line))) 530 531(defun hif-find-previous-relevant () 532 "Move to previous #if..., #else, or #endif, before the current line." 533 ;; (message "hif-find-previous-relevant at %d" (point)) 534 (beginning-of-line) 535 ;; avoid infinite recursion by only going to beginning of line if match found 536 (if (re-search-backward hif-ifx-else-endif-regexp (point-min) t) 537 (beginning-of-line))) 538 539 540(defun hif-looking-at-ifX () ;; Should eventually see #if 541 (looking-at hif-ifx-regexp)) 542(defun hif-looking-at-endif () 543 (looking-at hif-endif-regexp)) 544(defun hif-looking-at-else () 545 (looking-at hif-else-regexp)) 546 547 548 549(defun hif-ifdef-to-endif () 550 "If positioned at #ifX or #else form, skip to corresponding #endif." 551 ;; (message "hif-ifdef-to-endif at %d" (point)) (sit-for 1) 552 (hif-find-next-relevant) 553 (cond ((hif-looking-at-ifX) 554 (hif-ifdef-to-endif) ; find endif of nested if 555 (hif-ifdef-to-endif)) ; find outer endif or else 556 ((hif-looking-at-else) 557 (hif-ifdef-to-endif)) ; find endif following else 558 ((hif-looking-at-endif) 559 'done) 560 (t 561 (error "Mismatched #ifdef #endif pair")))) 562 563 564(defun hif-endif-to-ifdef () 565 "If positioned at #endif form, skip backward to corresponding #ifX." 566 ;; (message "hif-endif-to-ifdef at %d" (point)) 567 (let ((start (point))) 568 (hif-find-previous-relevant) 569 (if (= start (point)) 570 (error "Mismatched #ifdef #endif pair"))) 571 (cond ((hif-looking-at-endif) 572 (hif-endif-to-ifdef) ; find beginning of nested if 573 (hif-endif-to-ifdef)) ; find beginning of outer if or else 574 ((hif-looking-at-else) 575 (hif-endif-to-ifdef)) 576 ((hif-looking-at-ifX) 577 'done) 578 (t))) ; never gets here 579 580 581(defun forward-ifdef (&optional arg) 582 "Move point to beginning of line of the next ifdef-endif. 583With argument, do this that many times." 584 (interactive "p") 585 (or arg (setq arg 1)) 586 (if (< arg 0) (backward-ifdef (- arg)) 587 (while (< 0 arg) 588 (setq arg (- arg)) 589 (let ((start (point))) 590 (unless (hif-looking-at-ifX) 591 (hif-find-next-relevant)) 592 (if (hif-looking-at-ifX) 593 (hif-ifdef-to-endif) 594 (goto-char start) 595 (error "No following #ifdef")))))) 596 597 598(defun backward-ifdef (&optional arg) 599 "Move point to beginning of the previous ifdef-endif. 600With argument, do this that many times." 601 (interactive "p") 602 (or arg (setq arg 1)) 603 (if (< arg 0) (forward-ifdef (- arg)) 604 (while (< 0 arg) 605 (setq arg (1- arg)) 606 (beginning-of-line) 607 (let ((start (point))) 608 (unless (hif-looking-at-endif) 609 (hif-find-previous-relevant)) 610 (if (hif-looking-at-endif) 611 (hif-endif-to-ifdef) 612 (goto-char start) 613 (error "No previous #ifdef")))))) 614 615 616(defun down-ifdef () 617 "Move point to beginning of nested ifdef or else-part." 618 (interactive) 619 (let ((start (point))) 620 (hif-find-next-relevant) 621 (if (or (hif-looking-at-ifX) (hif-looking-at-else)) 622 () 623 (goto-char start) 624 (error "No following #ifdef")))) 625 626 627(defun up-ifdef () 628 "Move point to beginning of enclosing ifdef or else-part." 629 (interactive) 630 (beginning-of-line) 631 (let ((start (point))) 632 (unless (hif-looking-at-endif) 633 (hif-find-previous-relevant)) 634 (if (hif-looking-at-endif) 635 (hif-endif-to-ifdef)) 636 (if (= start (point)) 637 (error "No previous #ifdef")))) 638 639(defun next-ifdef (&optional arg) 640 "Move to the beginning of the next #ifX, #else, or #endif. 641With argument, do this that many times." 642 (interactive "p") 643 (or arg (setq arg 1)) 644 (if (< arg 0) (previous-ifdef (- arg)) 645 (while (< 0 arg) 646 (setq arg (1- arg)) 647 (hif-find-next-relevant) 648 (when (eolp) 649 (beginning-of-line) 650 (error "No following #ifdefs, #elses, or #endifs"))))) 651 652(defun previous-ifdef (&optional arg) 653 "Move to the beginning of the previous #ifX, #else, or #endif. 654With argument, do this that many times." 655 (interactive "p") 656 (or arg (setq arg 1)) 657 (if (< arg 0) (next-ifdef (- arg)) 658 (while (< 0 arg) 659 (setq arg (1- arg)) 660 (let ((start (point))) 661 (hif-find-previous-relevant) 662 (if (= start (point)) 663 (error "No previous #ifdefs, #elses, or #endifs")))))) 664 665 666;;===%%SF%% parsing (End) === 667 668 669;;===%%SF%% hide-ifdef-hiding (Start) === 670 671 672;;; A range is a structure with four components: 673;;; ELSE-P True if there was an else clause for the ifdef. 674;;; START The start of the range. (beginning of line) 675;;; ELSE The else marker (beginning of line) 676;;; Only valid if ELSE-P is true. 677;;; END The end of the range. (beginning of line) 678 679(defsubst hif-make-range (start end &optional else) 680 (list start else end)) 681 682(defsubst hif-range-start (range) (elt range 0)) 683(defsubst hif-range-else (range) (elt range 1)) 684(defsubst hif-range-end (range) (elt range 2)) 685 686 687 688;;; Find-Range 689;;; The workhorse, it delimits the #if region. Reasonably simple: 690;;; Skip until an #else or #endif is found, remembering positions. If 691;;; an #else was found, skip some more, looking for the true #endif. 692 693(defun hif-find-range () 694 "Return a Range structure describing the current #if region. 695Point is left unchanged." 696 ;; (message "hif-find-range at %d" (point)) 697 (save-excursion 698 (beginning-of-line) 699 (let ((start (point)) 700 (else nil) 701 (end nil)) 702 ;; Part one. Look for either #endif or #else. 703 ;; This loop-and-a-half dedicated to E. Dijkstra. 704 (while (progn 705 (hif-find-next-relevant) 706 (hif-looking-at-ifX)) ; Skip nested ifdef 707 (hif-ifdef-to-endif)) 708 ;; Found either a #else or an #endif. 709 (cond ((hif-looking-at-else) 710 (setq else (point))) 711 (t 712 (setq end (point)))) ; (save-excursion (end-of-line) (point)) 713 ;; If found #else, look for #endif. 714 (when else 715 (while (progn 716 (hif-find-next-relevant) 717 (hif-looking-at-ifX)) ; Skip nested ifdef 718 (hif-ifdef-to-endif)) 719 (if (hif-looking-at-else) 720 (error "Found two elses in a row? Broken!")) 721 (setq end (point))) ; (save-excursion (end-of-line) (point)) 722 (hif-make-range start end else)))) 723 724 725;;; A bit slimy. 726 727(defun hif-hide-line (point) 728 "Hide the line containing point. Does nothing if `hide-ifdef-lines' is nil." 729 (if hide-ifdef-lines 730 (save-excursion 731 (goto-char point) 732 (hide-ifdef-region-internal (line-beginning-position) 733 (progn (hif-end-of-line) (point)))))) 734 735 736;;; Hif-Possibly-Hide 737;;; There are four cases. The #ifX expression is "taken" if it 738;;; the hide-ifdef-evaluator returns T. Presumably, this means the code 739;;; inside the #ifdef would be included when the program was 740;;; compiled. 741;;; 742;;; Case 1: #ifX taken, and there's an #else. 743;;; The #else part must be hidden. The #if (then) part must be 744;;; processed for nested #ifX's. 745;;; Case 2: #ifX taken, and there's no #else. 746;;; The #if part must be processed for nested #ifX's. 747;;; Case 3: #ifX not taken, and there's an #else. 748;;; The #if part must be hidden. The #else part must be processed 749;;; for nested #ifs. 750;;; Case 4: #ifX not taken, and there's no #else. 751;;; The #ifX part must be hidden. 752;;; 753;;; Further processing is done by narrowing to the relevant region 754;;; and just recursively calling hide-ifdef-guts. 755;;; 756;;; When hif-possibly-hide returns, point is at the end of the 757;;; possibly-hidden range. 758 759(defun hif-recurse-on (start end) 760 "Call `hide-ifdef-guts' after narrowing to end of START line and END line." 761 (save-excursion 762 (save-restriction 763 (goto-char start) 764 (end-of-line) 765 (narrow-to-region (point) end) 766 (hide-ifdef-guts)))) 767 768(defun hif-possibly-hide () 769 "Called at #ifX expression, this hides those parts that should be hidden. 770It uses the judgement of `hide-ifdef-evaluator'." 771 ;; (message "hif-possibly-hide") (sit-for 1) 772 (let ((test (hif-canonicalize)) 773 (range (hif-find-range))) 774 ;; (message "test = %s" test) (sit-for 1) 775 776 (hif-hide-line (hif-range-end range)) 777 (if (not (hif-not (funcall hide-ifdef-evaluator test))) 778 (cond ((hif-range-else range) ; case 1 779 (hif-hide-line (hif-range-else range)) 780 (hide-ifdef-region (hif-range-else range) 781 (1- (hif-range-end range))) 782 (hif-recurse-on (hif-range-start range) 783 (hif-range-else range))) 784 (t ; case 2 785 (hif-recurse-on (hif-range-start range) 786 (hif-range-end range)))) 787 (cond ((hif-range-else range) ; case 3 788 (hif-hide-line (hif-range-else range)) 789 (hide-ifdef-region (hif-range-start range) 790 (1- (hif-range-else range))) 791 (hif-recurse-on (hif-range-else range) 792 (hif-range-end range))) 793 (t ; case 4 794 (hide-ifdef-region (point) 795 (1- (hif-range-end range)))))) 796 (hif-hide-line (hif-range-start range)) ; Always hide start. 797 (goto-char (hif-range-end range)) 798 (end-of-line))) 799 800 801 802(defun hide-ifdef-guts () 803 "Does most of the work of `hide-ifdefs'. 804It does not do the work that's pointless to redo on a recursive entry." 805 ;; (message "hide-ifdef-guts") 806 (save-excursion 807 (goto-char (point-min)) 808 (while (hif-find-any-ifX) 809 (hif-possibly-hide)))) 810 811;;===%%SF%% hide-ifdef-hiding (End) === 812 813 814;;===%%SF%% exports (Start) === 815 816;;;###autoload 817(defcustom hide-ifdef-initially nil 818 "*Non-nil means call `hide-ifdefs' when Hide-Ifdef mode is first activated." 819 :type 'boolean 820 :group 'hide-ifdef) 821 822;;;###autoload 823(defcustom hide-ifdef-read-only nil 824 "*Set to non-nil if you want buffer to be read-only while hiding text." 825 :type 'boolean 826 :group 'hide-ifdef) 827 828;;;###autoload 829(defcustom hide-ifdef-lines nil 830 "*Non-nil means hide the #ifX, #else, and #endif lines." 831 :type 'boolean 832 :group 'hide-ifdef) 833 834(defun hide-ifdef-toggle-read-only () 835 "Toggle `hide-ifdef-read-only'." 836 (interactive) 837 (setq hide-ifdef-read-only (not hide-ifdef-read-only)) 838 (message "Hide-Read-Only %s" 839 (if hide-ifdef-read-only "ON" "OFF")) 840 (if hide-ifdef-hiding 841 (setq buffer-read-only (or hide-ifdef-read-only hif-outside-read-only))) 842 (force-mode-line-update)) 843 844(defun hide-ifdef-toggle-outside-read-only () 845 "Replacement for `toggle-read-only' within Hide-Ifdef mode." 846 (interactive) 847 (setq hif-outside-read-only (not hif-outside-read-only)) 848 (message "Read only %s" 849 (if hif-outside-read-only "ON" "OFF")) 850 (setq buffer-read-only 851 (or (and hide-ifdef-hiding hide-ifdef-read-only) 852 hif-outside-read-only)) 853 (force-mode-line-update)) 854 855 856(defun hide-ifdef-define (var) 857 "Define a VAR so that #ifdef VAR would be included." 858 (interactive "SDefine what? ") 859 (hif-set-var var 1) 860 (if hide-ifdef-hiding (hide-ifdefs))) 861 862(defun hide-ifdef-undef (var) 863 "Undefine a VAR so that #ifdef VAR would not be included." 864 (interactive "SUndefine what? ") 865 (hif-set-var var nil) 866 (if hide-ifdef-hiding (hide-ifdefs))) 867 868 869(defun hide-ifdefs (&optional nomsg) 870 "Hide the contents of some #ifdefs. 871Assume that defined symbols have been added to `hide-ifdef-env'. 872The text hidden is the text that would not be included by the C 873preprocessor if it were given the file with those symbols defined. 874 875Turn off hiding by calling `show-ifdefs'." 876 877 (interactive) 878 (message "Hiding...") 879 (setq hif-outside-read-only buffer-read-only) 880 (unless hide-ifdef-mode (hide-ifdef-mode 1)) ; turn on hide-ifdef-mode 881 (if hide-ifdef-hiding 882 (show-ifdefs)) ; Otherwise, deep confusion. 883 (setq hide-ifdef-hiding t) 884 (hide-ifdef-guts) 885 (setq buffer-read-only (or hide-ifdef-read-only hif-outside-read-only)) 886 (or nomsg 887 (message "Hiding done"))) 888 889 890(defun show-ifdefs () 891 "Cancel the effects of `hide-ifdef': show the contents of all #ifdefs." 892 (interactive) 893 (setq buffer-read-only hif-outside-read-only) 894 (hif-show-all) 895 (setq hide-ifdef-hiding nil)) 896 897 898(defun hif-find-ifdef-block () 899 "Utility for hide and show `ifdef-block'. 900Return as (TOP . BOTTOM) the extent of ifdef block." 901 (let (max-bottom) 902 (cons (save-excursion 903 (beginning-of-line) 904 (unless (or (hif-looking-at-else) (hif-looking-at-ifX)) 905 (up-ifdef)) 906 (prog1 (point) 907 (hif-ifdef-to-endif) 908 (setq max-bottom (1- (point))))) 909 (save-excursion 910 (beginning-of-line) 911 (unless (hif-looking-at-endif) 912 (hif-find-next-relevant)) 913 (while (hif-looking-at-ifX) 914 (hif-ifdef-to-endif) 915 (hif-find-next-relevant)) 916 (min max-bottom (1- (point))))))) 917 918 919(defun hide-ifdef-block () 920 "Hide the ifdef block (true or false part) enclosing or before the cursor." 921 (interactive) 922 (unless hide-ifdef-mode (hide-ifdef-mode 1)) 923 (let ((top-bottom (hif-find-ifdef-block))) 924 (hide-ifdef-region (car top-bottom) (cdr top-bottom)) 925 (when hide-ifdef-lines 926 (hif-hide-line (car top-bottom)) 927 (hif-hide-line (1+ (cdr top-bottom)))) 928 (setq hide-ifdef-hiding t)) 929 (setq buffer-read-only (or hide-ifdef-read-only hif-outside-read-only))) 930 931(defun show-ifdef-block () 932 "Show the ifdef block (true or false part) enclosing or before the cursor." 933 (interactive) 934 (let ((top-bottom (hif-find-ifdef-block))) 935 (if hide-ifdef-lines 936 (hif-show-ifdef-region 937 (save-excursion 938 (goto-char (car top-bottom)) (line-beginning-position)) 939 (save-excursion 940 (goto-char (1+ (cdr top-bottom))) 941 (hif-end-of-line) (point))) 942 (hif-show-ifdef-region (1- (car top-bottom)) (cdr top-bottom))))) 943 944 945;;; definition alist support 946 947(defvar hide-ifdef-define-alist nil 948 "A global assoc list of pre-defined symbol lists.") 949 950(defun hif-compress-define-list (env) 951 "Compress the define list ENV into a list of defined symbols only." 952 (let ((new-defs nil)) 953 (dolist (def env new-defs) 954 (if (hif-lookup (car def)) (push (car env) new-defs))))) 955 956(defun hide-ifdef-set-define-alist (name) 957 "Set the association for NAME to `hide-ifdef-env'." 958 (interactive "SSet define list: ") 959 (push (cons name (hif-compress-define-list hide-ifdef-env)) 960 hide-ifdef-define-alist)) 961 962(defun hide-ifdef-use-define-alist (name) 963 "Set `hide-ifdef-env' to the define list specified by NAME." 964 (interactive 965 (list (completing-read "Use define list: " 966 (mapcar (lambda (x) (symbol-name (car x))) 967 hide-ifdef-define-alist) 968 nil t))) 969 (if (stringp name) (setq name (intern name))) 970 (let ((define-list (assoc name hide-ifdef-define-alist))) 971 (if define-list 972 (setq hide-ifdef-env 973 (mapcar (lambda (arg) (cons arg t)) 974 (cdr define-list))) 975 (error "No define list for %s" name)) 976 (if hide-ifdef-hiding (hide-ifdefs)))) 977 978(provide 'hideif) 979 980;; arch-tag: c6381d17-a59a-483a-b945-658f22277981 981;;; hideif.el ends here 982