(dcl-mode-syntax-table): Add entry for backslash.
[bpt/emacs.git] / lisp / emacs-lisp / ewoc.el
CommitLineData
e8af40ee 1;;; ewoc.el --- utility to maintain a view of a list of objects in a buffer
5b467bf4 2
0111ab41
JB
3;; Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 04
4;; Free Software Foundation
5b467bf4
SM
5
6;; Author: Per Cederqvist <ceder@lysator.liu.se>
7;; Inge Wallin <inge@lysator.liu.se>
8;; Maintainer: monnier@gnu.org
9;; Created: 3 Aug 1992
10;; Keywords: extensions, lisp
11
12;; This file is part of GNU Emacs.
13
14;; GNU Emacs is free software; you can redistribute it and/or modify
15;; it under the terms of the GNU General Public License as published by
16;; the Free Software Foundation; either version 2, or (at your option)
17;; any later version.
18
19;; GNU Emacs is distributed in the hope that it will be useful,
20;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22;; GNU General Public License for more details.
23
24;; You should have received a copy of the GNU General Public License
25;; along with GNU Emacs; see the file COPYING. If not, write to the
26;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
27;; Boston, MA 02111-1307, USA.
28
29;;; Commentary:
30
31;; Ewoc Was Once Cookie
32;; But now it's Emacs' Widget for Object Collections
33
34;; As the name implies this derives from the `cookie' package (part
10c471e6 35;; of Elib). The changes are pervasive though mostly superficial:
5b467bf4 36
10c471e6 37;; - uses CL (and its `defstruct')
5b467bf4
SM
38;; - separate from Elib.
39;; - uses its own version of a doubly-linked list which allows us
40;; to merge the elib-wrapper and the elib-node structures into ewoc-node
41;; - dropping functions not used by PCL-CVS (the only client of ewoc at the
42;; time of writing)
43;; - removing unused arguments
44;; - renaming:
45;; elib-node ==> ewoc--node
46;; collection ==> ewoc
47;; tin ==> ewoc--node
48;; cookie ==> data or element or elem
49
50;; Introduction
51;; ============
52;;
53;; Ewoc is a package that implements a connection between an
54;; dll (a doubly linked list) and the contents of a buffer.
55;; Possible uses are dired (have all files in a list, and show them),
56;; buffer-list, kom-prioritize (in the LysKOM elisp client) and
57;; others. pcl-cvs.el uses ewoc.el.
58;;
59;; Ewoc can be considered as the `view' part of a model-view-controller.
60;;
61;; A `element' can be any lisp object. When you use the ewoc
62;; package you specify a pretty-printer, a function that inserts
63;; a printable representation of the element in the buffer. (The
64;; pretty-printer should use "insert" and not
65;; "insert-before-markers").
66;;
67;; A `ewoc' consists of a doubly linked list of elements, a
68;; header, a footer and a pretty-printer. It is displayed at a
69;; certain point in a certain buffer. (The buffer and point are
70;; fixed when the ewoc is created). The header and the footer
71;; are constant strings. They appear before and after the elements.
5b467bf4
SM
72;;
73;; Ewoc does not affect the mode of the buffer in any way. It
74;; merely makes it easy to connect an underlying data representation
75;; to the buffer contents.
76;;
77;; A `ewoc--node' is an object that contains one element. There are
10c471e6
SM
78;; functions in this package that given an ewoc--node extract the data, or
79;; give the next or previous ewoc--node. (All ewoc--nodes are linked together
80;; in a doubly linked list. The `previous' ewoc--node is the one that appears
5b467bf4
SM
81;; before the other in the buffer.) You should not do anything with
82;; an ewoc--node except pass it to the functions in this package.
83;;
84;; An ewoc is a very dynamic thing. You can easily add or delete elements.
85;; You can apply a function to all elements in an ewoc, etc, etc.
86;;
87;; Remember that an element can be anything. Your imagination is the
88;; limit! It is even possible to have another ewoc as an
89;; element. In that way some kind of tree hierarchy can be created.
90;;
91;; Full documentation will, God willing, soon be available in a
92;; Texinfo manual.
93
94;; In the mean time `grep '^(.*ewoc-[^-]' emacs-lisp/ewoc.el' can help
95;; you find all the exported functions:
a1506d29 96;;
cb3430a1 97;; (defun ewoc-create (pretty-printer &optional header footer)
5b467bf4 98;; (defalias 'ewoc-data 'ewoc--node-data)
10c471e6 99;; (defun ewoc-location (node)
5b467bf4
SM
100;; (defun ewoc-enter-first (ewoc data)
101;; (defun ewoc-enter-last (ewoc data)
102;; (defun ewoc-enter-after (ewoc node data)
103;; (defun ewoc-enter-before (ewoc node data)
104;; (defun ewoc-next (ewoc node)
105;; (defun ewoc-prev (ewoc node)
106;; (defun ewoc-nth (ewoc n)
107;; (defun ewoc-map (map-function ewoc &rest args)
108;; (defun ewoc-filter (ewoc predicate &rest args)
44946a4c 109;; (defun ewoc-locate (ewoc &optional pos guess)
5b467bf4 110;; (defun ewoc-invalidate (ewoc &rest nodes)
44946a4c
SM
111;; (defun ewoc-goto-prev (ewoc arg)
112;; (defun ewoc-goto-next (ewoc arg)
5b467bf4
SM
113;; (defun ewoc-goto-node (ewoc node)
114;; (defun ewoc-refresh (ewoc)
115;; (defun ewoc-collect (ewoc predicate &rest args)
116;; (defun ewoc-buffer (ewoc)
cb3430a1
SM
117;; (defun ewoc-get-hf (ewoc)
118;; (defun ewoc-set-hf (ewoc header footer)
5b467bf4
SM
119
120;; Coding conventions
121;; ==================
122;;
123;; All functions of course start with `ewoc'. Functions and macros
124;; starting with the prefix `ewoc--' are meant for internal use,
125;; while those starting with `ewoc-' are exported for public use.
126;; There are currently no global or buffer-local variables used.
127
128
129;;; Code:
130
131(eval-when-compile (require 'cl)) ;because of CL compiler macros
132
133;; The doubly linked list is implemented as a circular list
134;; with a dummy node first and last. The dummy node is used as
135;; "the dll" (or rather is the dll handle passed around).
136
137(defstruct (ewoc--node
138 (:type vector) ;required for ewoc--node-branch hack
139 (:constructor ewoc--node-create (start-marker data)))
140 left right data start-marker)
141
21311ac9
SM
142(defalias 'ewoc--node-branch 'aref
143 "Get the left (CHILD=0) or right (CHILD=1) child of the NODE.
144
145\(fn NODE CHILD)")
5b467bf4
SM
146
147(defun ewoc--dll-create ()
148 "Create an empty doubly linked list."
149 (let ((dummy-node (ewoc--node-create 'DL-LIST 'DL-LIST)))
150 (setf (ewoc--node-right dummy-node) dummy-node)
151 (setf (ewoc--node-left dummy-node) dummy-node)
152 dummy-node))
153
154(defun ewoc--node-enter-before (node elemnode)
155 "Insert ELEMNODE before NODE in a DLL."
156 (assert (and (null (ewoc--node-left elemnode)) (null (ewoc--node-right elemnode))))
157 (setf (ewoc--node-left elemnode) (ewoc--node-left node))
158 (setf (ewoc--node-right elemnode) node)
159 (setf (ewoc--node-right (ewoc--node-left node)) elemnode)
160 (setf (ewoc--node-left node) elemnode))
161
162(defun ewoc--node-enter-first (dll node)
163 "Add a free floating NODE first in DLL."
164 (ewoc--node-enter-before (ewoc--node-right dll) node))
165
166(defun ewoc--node-enter-last (dll node)
167 "Add a free floating NODE last in DLL."
168 (ewoc--node-enter-before dll node))
169
170(defun ewoc--node-next (dll node)
171 "Return the node after NODE, or nil if NODE is the last node."
172 (unless (eq (ewoc--node-right node) dll) (ewoc--node-right node)))
173
174(defun ewoc--node-prev (dll node)
175 "Return the node before NODE, or nil if NODE is the first node."
176 (unless (eq (ewoc--node-left node) dll) (ewoc--node-left node)))
177
178(defun ewoc--node-delete (node)
179 "Unbind NODE from its doubly linked list and return it."
180 ;; This is a no-op when applied to the dummy node. This will return
181 ;; nil if applied to the dummy node since it always contains nil.
182 (setf (ewoc--node-right (ewoc--node-left node)) (ewoc--node-right node))
183 (setf (ewoc--node-left (ewoc--node-right node)) (ewoc--node-left node))
184 (setf (ewoc--node-left node) nil)
185 (setf (ewoc--node-right node) nil)
186 node)
187
188(defun ewoc--node-nth (dll n)
189 "Return the Nth node from the doubly linked list DLL.
190N counts from zero. If DLL is not that long, nil is returned.
191If N is negative, return the -(N+1)th last element.
192Thus, (ewoc--node-nth dll 0) returns the first node,
193and (ewoc--node-nth dll -1) returns the last node."
194 ;; Branch 0 ("follow left pointer") is used when n is negative.
195 ;; Branch 1 ("follow right pointer") is used otherwise.
196 (let* ((branch (if (< n 0) 0 1))
197 (node (ewoc--node-branch dll branch)))
198 (if (< n 0) (setq n (- -1 n)))
199 (while (and (not (eq dll node)) (> n 0))
200 (setq node (ewoc--node-branch node branch))
201 (setq n (1- n)))
202 (unless (eq dll node) node)))
203
10c471e6
SM
204(defun ewoc-location (node)
205 "Return the start location of NODE."
206 (ewoc--node-start-marker node))
207
5b467bf4
SM
208\f
209;;; The ewoc data type
210
211(defstruct (ewoc
212 (:constructor nil)
213 (:constructor ewoc--create
214 (buffer pretty-printer header footer dll))
215 (:conc-name ewoc--))
216 buffer pretty-printer header footer dll last-node)
217
218(defmacro ewoc--set-buffer-bind-dll-let* (ewoc varlist &rest forms)
219 "Execute FORMS with ewoc--buffer selected as current buffer,
220dll bound to ewoc--dll, and VARLIST bound as in a let*.
221dll will be bound when VARLIST is initialized, but the current
222buffer will *not* have been changed.
223Return value of last form in FORMS."
224 (let ((old-buffer (make-symbol "old-buffer"))
225 (hnd (make-symbol "ewoc")))
8a946354
SS
226 `(let* ((,old-buffer (current-buffer))
227 (,hnd ,ewoc)
228 (dll (ewoc--dll ,hnd))
229 ,@varlist)
230 (set-buffer (ewoc--buffer ,hnd))
231 (unwind-protect
232 (progn ,@forms)
233 (set-buffer ,old-buffer)))))
5b467bf4
SM
234
235(defmacro ewoc--set-buffer-bind-dll (ewoc &rest forms)
236 `(ewoc--set-buffer-bind-dll-let* ,ewoc nil ,@forms))
237
238(defsubst ewoc--filter-hf-nodes (ewoc node)
239 "Evaluate NODE once and return it.
240BUT if it is the header or the footer in EWOC return nil instead."
241 (unless (or (eq node (ewoc--header ewoc))
242 (eq node (ewoc--footer ewoc)))
243 node))
244
245
5b467bf4
SM
246(defun ewoc--create-node (data pretty-printer pos)
247 "Call PRETTY-PRINTER with point set at POS in current buffer.
0111ab41 248Remember the start position. Create a wrapper containing that
5b467bf4
SM
249start position and the element DATA."
250 (save-excursion
251 ;; Remember the position as a number so that it doesn't move
252 ;; when we insert the string.
253 (when (markerp pos) (setq pos (marker-position pos)))
254 (goto-char pos)
255 (let ((inhibit-read-only t))
256 ;; Insert the trailing newline using insert-before-markers
257 ;; so that the start position for the next element is updated.
258 (insert-before-markers ?\n)
259 ;; Move back, and call the pretty-printer.
260 (backward-char 1)
261 (funcall pretty-printer data)
262 (ewoc--node-create (copy-marker pos) data))))
263
264
265(defun ewoc--delete-node-internal (ewoc node)
266 "Delete a data string from EWOC.
0111ab41 267Can not be used on the footer. Returns the wrapper that is deleted.
5b467bf4
SM
268The start-marker in the wrapper is set to nil, so that it doesn't
269consume any more resources."
270 (let ((dll (ewoc--dll ewoc))
271 (inhibit-read-only t))
272 ;; If we are about to delete the node pointed at by last-node,
273 ;; set last-node to nil.
274 (if (eq (ewoc--last-node ewoc) node)
275 (setf (ewoc--last-node ewoc) nil))
276
277 (delete-region (ewoc--node-start-marker node)
278 (ewoc--node-start-marker (ewoc--node-next dll node)))
279 (set-marker (ewoc--node-start-marker node) nil)
280 ;; Delete the node, and return the wrapper.
281 (ewoc--node-delete node)))
282
283
cb3430a1
SM
284(defun ewoc--refresh-node (pp node)
285 "Redisplay the element represented by NODE using the pretty-printer PP."
5b467bf4
SM
286 (let ((inhibit-read-only t))
287 (save-excursion
288 ;; First, remove the string from the buffer:
289 (delete-region (ewoc--node-start-marker node)
290 (1- (marker-position
cb3430a1 291 (ewoc--node-start-marker (ewoc--node-right node)))))
5b467bf4
SM
292 ;; Calculate and insert the string.
293 (goto-char (ewoc--node-start-marker node))
cb3430a1 294 (funcall pp (ewoc--node-data node)))))
5b467bf4
SM
295\f
296;;; ===========================================================================
297;;; Public members of the Ewoc package
298
299
cb3430a1 300(defun ewoc-create (pretty-printer &optional header footer)
5b467bf4
SM
301 "Create an empty ewoc.
302
cb3430a1 303The ewoc will be inserted in the current buffer at the current position.
5b467bf4
SM
304
305PRETTY-PRINTER should be a function that takes one argument, an
306element, and inserts a string representing it in the buffer (at
0111ab41
JB
307point). The string PRETTY-PRINTER inserts may be empty or span
308several lines. A trailing newline will always be inserted
309automatically. The PRETTY-PRINTER should use `insert', and not
310`insert-before-markers'.
311
312Optional second argument HEADER is a string that will always be
313present at the top of the ewoc. HEADER should end with a
314newline. Optional third argument FOOTER is similar, and will
cb3430a1 315be inserted at the bottom of the ewoc."
5b467bf4 316 (let ((new-ewoc
cb3430a1
SM
317 (ewoc--create (current-buffer)
318 pretty-printer nil nil (ewoc--dll-create)))
319 (pos (point)))
5b467bf4
SM
320 (ewoc--set-buffer-bind-dll new-ewoc
321 ;; Set default values
322 (unless header (setq header ""))
323 (unless footer (setq footer ""))
cb3430a1
SM
324 (setf (ewoc--node-start-marker dll) (copy-marker pos))
325 (let ((foot (ewoc--create-node footer (lambda (x) (insert footer)) pos))
326 (head (ewoc--create-node header (lambda (x) (insert header)) pos)))
5b467bf4
SM
327 (ewoc--node-enter-first dll head)
328 (ewoc--node-enter-last dll foot)
cb3430a1
SM
329 (setf (ewoc--header new-ewoc) head)
330 (setf (ewoc--footer new-ewoc) foot)))
5b467bf4
SM
331 ;; Return the ewoc
332 new-ewoc))
333
334(defalias 'ewoc-data 'ewoc--node-data)
335
336(defun ewoc-enter-first (ewoc data)
337 "Enter DATA first in EWOC."
338 (ewoc--set-buffer-bind-dll ewoc
339 (ewoc-enter-after ewoc (ewoc--node-nth dll 0) data)))
340
341(defun ewoc-enter-last (ewoc data)
342 "Enter DATA last in EWOC."
343 (ewoc--set-buffer-bind-dll ewoc
344 (ewoc-enter-before ewoc (ewoc--node-nth dll -1) data)))
345
346
347(defun ewoc-enter-after (ewoc node data)
10c471e6
SM
348 "Enter a new element DATA after NODE in EWOC.
349Returns the new NODE."
5b467bf4
SM
350 (ewoc--set-buffer-bind-dll ewoc
351 (ewoc-enter-before ewoc (ewoc--node-next dll node) data)))
352
353(defun ewoc-enter-before (ewoc node data)
10c471e6
SM
354 "Enter a new element DATA before NODE in EWOC.
355Returns the new NODE."
5b467bf4
SM
356 (ewoc--set-buffer-bind-dll ewoc
357 (ewoc--node-enter-before
358 node
359 (ewoc--create-node
360 data
361 (ewoc--pretty-printer ewoc)
362 (ewoc--node-start-marker node)))))
363
364(defun ewoc-next (ewoc node)
365 "Get the next node.
366Returns nil if NODE is nil or the last element."
367 (when node
368 (ewoc--filter-hf-nodes
369 ewoc (ewoc--node-next (ewoc--dll ewoc) node))))
370
371(defun ewoc-prev (ewoc node)
372 "Get the previous node.
373Returns nil if NODE is nil or the first element."
374 (when node
375 (ewoc--filter-hf-nodes
376 ewoc
377 (ewoc--node-prev (ewoc--dll ewoc) node))))
378
379
380(defun ewoc-nth (ewoc n)
381 "Return the Nth node.
f0529b5b 382N counts from zero. Return nil if there is less than N elements.
5b467bf4
SM
383If N is negative, return the -(N+1)th last element.
384Thus, (ewoc-nth dll 0) returns the first node,
385and (ewoc-nth dll -1) returns the last node.
386Use `ewoc--node-data' to extract the data from the node."
387 ;; Skip the header (or footer, if n is negative).
388 (setq n (if (< n 0) (1- n) (1+ n)))
389 (ewoc--filter-hf-nodes ewoc
390 (ewoc--node-nth (ewoc--dll ewoc) n)))
391
392(defun ewoc-map (map-function ewoc &rest args)
393 "Apply MAP-FUNCTION to all elements in EWOC.
394MAP-FUNCTION is applied to the first element first.
395If MAP-FUNCTION returns non-nil the element will be refreshed (its
396pretty-printer will be called once again).
397
0111ab41
JB
398Note that the buffer for EWOC will be the current buffer when
399MAP-FUNCTION is called. MAP-FUNCTION must restore the current
400buffer before it returns, if it changes it.
5b467bf4
SM
401
402If more than two arguments are given, the remaining
403arguments will be passed to MAP-FUNCTION."
404 (ewoc--set-buffer-bind-dll-let* ewoc
405 ((footer (ewoc--footer ewoc))
406 (node (ewoc--node-nth dll 1)))
407 (while (not (eq node footer))
408 (if (apply map-function (ewoc--node-data node) args)
cb3430a1 409 (ewoc--refresh-node (ewoc--pretty-printer ewoc) node))
5b467bf4
SM
410 (setq node (ewoc--node-next dll node)))))
411
412(defun ewoc-filter (ewoc predicate &rest args)
413 "Remove all elements in EWOC for which PREDICATE returns nil.
a1506d29 414Note that the buffer for EWOC will be current-buffer when PREDICATE
0111ab41 415is called. PREDICATE must restore the current buffer before it returns
5b467bf4 416if it changes it.
0111ab41 417The PREDICATE is called with the element as its first argument. If any
5b467bf4
SM
418ARGS are given they will be passed to the PREDICATE."
419 (ewoc--set-buffer-bind-dll-let* ewoc
420 ((node (ewoc--node-nth dll 1))
421 (footer (ewoc--footer ewoc))
422 (next nil))
423 (while (not (eq node footer))
424 (setq next (ewoc--node-next dll node))
425 (unless (apply predicate (ewoc--node-data node) args)
426 (ewoc--delete-node-internal ewoc node))
427 (setq node next))))
428
44946a4c 429(defun ewoc-locate (ewoc &optional pos guess)
5b467bf4 430 "Return the node that POS (a buffer position) is within.
44946a4c 431POS may be a marker or an integer. It defaults to point.
0111ab41 432GUESS should be a node that it is likely to be near POS.
5b467bf4
SM
433
434If POS points before the first element, the first node is returned.
435If POS points after the last element, the last node is returned.
436If the EWOC is empty, nil is returned."
44946a4c 437 (unless pos (setq pos (point)))
5b467bf4
SM
438 (ewoc--set-buffer-bind-dll-let* ewoc
439 ((footer (ewoc--footer ewoc)))
440
441 (cond
442 ;; Nothing present?
443 ((eq (ewoc--node-nth dll 1) (ewoc--node-nth dll -1))
444 nil)
445
446 ;; Before second elem?
447 ((< pos (ewoc--node-start-marker (ewoc--node-nth dll 2)))
448 (ewoc--node-nth dll 1))
449
450 ;; After one-before-last elem?
451 ((>= pos (ewoc--node-start-marker (ewoc--node-nth dll -2)))
452 (ewoc--node-nth dll -2))
453
454 ;; We now know that pos is within a elem.
455 (t
456 ;; Make an educated guess about which of the three known
457 ;; node'es (the first, the last, or GUESS) is nearest.
458 (let* ((best-guess (ewoc--node-nth dll 1))
459 (distance (abs (- pos (ewoc--node-start-marker best-guess)))))
460 (when guess
461 (let ((d (abs (- pos (ewoc--node-start-marker guess)))))
462 (when (< d distance)
463 (setq distance d)
464 (setq best-guess guess))))
465
466 (let* ((g (ewoc--node-nth dll -1)) ;Check the last elem
467 (d (abs (- pos (ewoc--node-start-marker g)))))
468 (when (< d distance)
469 (setq distance d)
470 (setq best-guess g)))
471
472 (when (ewoc--last-node ewoc) ;Check "previous".
473 (let* ((g (ewoc--last-node ewoc))
474 (d (abs (- pos (ewoc--node-start-marker g)))))
475 (when (< d distance)
476 (setq distance d)
477 (setq best-guess g))))
478
479 ;; best-guess is now a "best guess".
480 ;; Find the correct node. First determine in which direction
481 ;; it lies, and then move in that direction until it is found.
a1506d29 482
5b467bf4
SM
483 (cond
484 ;; Is pos after the guess?
485 ((>= pos
486 (ewoc--node-start-marker best-guess))
487 ;; Loop until we are exactly one node too far down...
488 (while (>= pos (ewoc--node-start-marker best-guess))
489 (setq best-guess (ewoc--node-next dll best-guess)))
490 ;; ...and return the previous node.
491 (ewoc--node-prev dll best-guess))
492
493 ;; Pos is before best-guess
494 (t
495 (while (< pos (ewoc--node-start-marker best-guess))
496 (setq best-guess (ewoc--node-prev dll best-guess)))
497 best-guess)))))))
498
499(defun ewoc-invalidate (ewoc &rest nodes)
500 "Refresh some elements.
0111ab41 501The pretty-printer set for EWOC will be called for all NODES."
5b467bf4
SM
502 (ewoc--set-buffer-bind-dll ewoc
503 (dolist (node nodes)
cb3430a1 504 (ewoc--refresh-node (ewoc--pretty-printer ewoc) node))))
5b467bf4 505
44946a4c 506(defun ewoc-goto-prev (ewoc arg)
5b467bf4
SM
507 "Move point to the ARGth previous element.
508Don't move if we are at the first element, or if EWOC is empty.
509Returns the node we moved to."
510 (ewoc--set-buffer-bind-dll-let* ewoc
6d84ac85 511 ((node (ewoc-locate ewoc (point))))
5b467bf4 512 (when node
44946a4c
SM
513 ;; If we were past the last element, first jump to it.
514 (when (>= (point) (ewoc--node-start-marker (ewoc--node-right node)))
515 (setq arg (1- arg)))
5b467bf4
SM
516 (while (and node (> arg 0))
517 (setq arg (1- arg))
518 (setq node (ewoc--node-prev dll node)))
519 ;; Never step above the first element.
520 (unless (ewoc--filter-hf-nodes ewoc node)
521 (setq node (ewoc--node-nth dll 1)))
522 (ewoc-goto-node ewoc node))))
523
44946a4c 524(defun ewoc-goto-next (ewoc arg)
5b467bf4 525 "Move point to the ARGth next element.
44946a4c 526Returns the node (or nil if we just passed the last node)."
5b467bf4 527 (ewoc--set-buffer-bind-dll-let* ewoc
6d84ac85 528 ((node (ewoc-locate ewoc (point))))
5b467bf4
SM
529 (while (and node (> arg 0))
530 (setq arg (1- arg))
531 (setq node (ewoc--node-next dll node)))
532 ;; Never step below the first element.
44946a4c
SM
533 ;; (unless (ewoc--filter-hf-nodes ewoc node)
534 ;; (setq node (ewoc--node-nth dll -2)))
5b467bf4
SM
535 (ewoc-goto-node ewoc node)))
536
537(defun ewoc-goto-node (ewoc node)
538 "Move point to NODE."
539 (ewoc--set-buffer-bind-dll ewoc
540 (goto-char (ewoc--node-start-marker node))
541 (if goal-column (move-to-column goal-column))
542 (setf (ewoc--last-node ewoc) node)))
543
544(defun ewoc-refresh (ewoc)
545 "Refresh all data in EWOC.
546The pretty-printer that was specified when the EWOC was created
547will be called for all elements in EWOC.
548Note that `ewoc-invalidate' is more efficient if only a small
549number of elements needs to be refreshed."
550 (ewoc--set-buffer-bind-dll-let* ewoc
cb3430a1 551 ((footer (ewoc--footer ewoc)))
5b467bf4
SM
552 (let ((inhibit-read-only t))
553 (delete-region (ewoc--node-start-marker (ewoc--node-nth dll 1))
554 (ewoc--node-start-marker footer))
555 (goto-char (ewoc--node-start-marker footer))
556 (let ((node (ewoc--node-nth dll 1)))
557 (while (not (eq node footer))
558 (set-marker (ewoc--node-start-marker node) (point))
559 (funcall (ewoc--pretty-printer ewoc)
560 (ewoc--node-data node))
561 (insert "\n")
562 (setq node (ewoc--node-next dll node)))))
563 (set-marker (ewoc--node-start-marker footer) (point))))
564
565(defun ewoc-collect (ewoc predicate &rest args)
566 "Select elements from EWOC using PREDICATE.
567Return a list of all selected data elements.
0111ab41
JB
568PREDICATE is a function that takes a data element as its first
569argument. The elements on the returned list will appear in the
570same order as in the buffer. You should not rely on the order of
571calls to PREDICATE.
572Note that the buffer the EWOC is displayed in is the current
573buffer when PREDICATE is called. PREDICATE must restore it if it
574changes it.
5b467bf4
SM
575If more than two arguments are given the
576remaining arguments will be passed to PREDICATE."
577 (ewoc--set-buffer-bind-dll-let* ewoc
578 ((header (ewoc--header ewoc))
579 (node (ewoc--node-nth dll -2))
580 result)
581 (while (not (eq node header))
582 (if (apply predicate (ewoc--node-data node) args)
583 (push (ewoc--node-data node) result))
584 (setq node (ewoc--node-prev dll node)))
6d84ac85 585 (nreverse result)))
5b467bf4
SM
586
587(defun ewoc-buffer (ewoc)
588 "Return the buffer that is associated with EWOC.
589Returns nil if the buffer has been deleted."
590 (let ((buf (ewoc--buffer ewoc)))
591 (when (buffer-name buf) buf)))
592
cb3430a1
SM
593(defun ewoc-get-hf (ewoc)
594 "Return a cons cell containing the (HEADER . FOOTER) of EWOC."
595 (cons (ewoc--node-data (ewoc--header ewoc))
596 (ewoc--node-data (ewoc--footer ewoc))))
597
598(defun ewoc-set-hf (ewoc header footer)
599 "Set the HEADER and FOOTER of EWOC."
600 (setf (ewoc--node-data (ewoc--header ewoc)) header)
601 (setf (ewoc--node-data (ewoc--footer ewoc)) footer)
602 (ewoc--refresh-node (lambda (x) (insert header)) (ewoc--header ewoc))
603 (ewoc--refresh-node (lambda (x) (insert footer)) (ewoc--footer ewoc)))
604
5b467bf4
SM
605\f
606(provide 'ewoc)
607
608;;; Local Variables:
609;;; eval: (put 'ewoc--set-buffer-bind-dll 'lisp-indent-hook 1)
610;;; eval: (put 'ewoc--set-buffer-bind-dll-let* 'lisp-indent-hook 2)
611;;; End:
612
ab5796a9 613;;; arch-tag: d78915b9-9a07-44bf-aac6-04a1fc1bd6d4
5b467bf4 614;;; ewoc.el ends here