view lisp/list-mode.el @ 826:6728e641994e

[xemacs-hg @ 2002-05-05 11:30:15 by ben] syntax cache, 8-bit-format, lots of code cleanup README.packages: Update info about --package-path. i.c: Create an inheritable event and pass it on to XEmacs, so that ^C can be handled properly. Intercept ^C and signal the event. "Stop Build" in VC++ now works. bytecomp-runtime.el: Doc string changes. compat.el: Some attempts to redo this to make it truly useful and fix the "multiple versions interacting with each other" problem. Not yet done. Currently doesn't work. files.el: Use with-obsolete-variable to avoid warnings in new revert-buffer code. xemacs.mak: Split up CFLAGS into a version without flags specifying the C library. The problem seems to be that minitar depends on zlib, which depends specifically on libc.lib, not on any of the other C libraries. Unless you compile with libc.lib, you get errors -- specifically, no _errno in the other libraries, which must make it something other than an int. (#### But this doesn't seem to obtain in XEmacs, which also uses zlib, and can be linked with any of the C libraries. Maybe zlib is used differently and doesn't need errno, or maybe XEmacs provides an int errno; ... I don't understand. Makefile.in.in: Fix so that packages are around when testing. abbrev.c, alloc.c, buffer.c, buffer.h, bytecode.c, callint.c, casefiddle.c, casetab.c, casetab.h, charset.h, chartab.c, chartab.h, cmds.c, console-msw.h, console-stream.c, console-x.c, console.c, console.h, data.c, device-msw.c, device.c, device.h, dialog-msw.c, dialog-x.c, dired-msw.c, dired.c, doc.c, doprnt.c, dumper.c, editfns.c, elhash.c, emacs.c, eval.c, event-Xt.c, event-gtk.c, event-msw.c, event-stream.c, events.c, events.h, extents.c, extents.h, faces.c, file-coding.c, file-coding.h, fileio.c, fns.c, font-lock.c, frame-gtk.c, frame-msw.c, frame-x.c, frame.c, frame.h, glade.c, glyphs-gtk.c, glyphs-msw.c, glyphs-msw.h, glyphs-x.c, glyphs.c, glyphs.h, gui-msw.c, gui-x.c, gui.h, gutter.h, hash.h, indent.c, insdel.c, intl-win32.c, intl.c, keymap.c, lisp-disunion.h, lisp-union.h, lisp.h, lread.c, lrecord.h, lstream.c, lstream.h, marker.c, menubar-gtk.c, menubar-msw.c, menubar-x.c, menubar.c, minibuf.c, mule-ccl.c, mule-charset.c, mule-coding.c, mule-wnnfns.c, nas.c, objects-msw.c, objects-x.c, opaque.c, postgresql.c, print.c, process-nt.c, process-unix.c, process.c, process.h, profile.c, rangetab.c, redisplay-gtk.c, redisplay-msw.c, redisplay-output.c, redisplay-x.c, redisplay.c, redisplay.h, regex.c, regex.h, scrollbar-msw.c, search.c, select-x.c, specifier.c, specifier.h, symbols.c, symsinit.h, syntax.c, syntax.h, syswindows.h, tests.c, text.c, text.h, tooltalk.c, ui-byhand.c, ui-gtk.c, unicode.c, win32.c, window.c: Another big Ben patch. -- FUNCTIONALITY CHANGES: add partial support for 8-bit-fixed, 16-bit-fixed, and 32-bit-fixed formats. not quite done yet. (in particular, needs functions to actually convert the buffer.) NOTE: lots of changes to regex.c here. also, many new *_fmt() inline funs that take an Internal_Format argument. redo syntax cache code. make the cache per-buffer; keep the cache valid across calls to functions that use it. also keep it valid across insertions/deletions and extent changes, as much as is possible. eliminate the junky regex-reentrancy code by passing in the relevant lisp info to the regex routines as local vars. add general mechanism in extents code for signalling extent changes. fix numerous problems with the case-table implementation; yoshiki never properly transferred many algorithms from old-style to new-style case tables. redo char tables to support a default argument, so that mapping only occurs over changed args. change many chartab functions to accept Lisp_Object instead of Lisp_Char_Table *. comment out the code in font-lock.c by default, because font-lock.el no longer uses it. we should consider eliminating it entirely. Don't output bell as ^G in console-stream when not a TTY. add -mswindows-termination-handle to interface with i.c, so we can properly kill a build. add more error-checking to buffer/string macros. add some additional buffer_or_string_() funs. -- INTERFACE CHANGES AFFECTING MORE CODE: switch the arguments of write_c_string and friends to be consistent with write_fmt_string, which must have printcharfun first. change BI_* macros to BYTE_* for increased clarity; similarly for bi_* local vars. change VOID_TO_LISP to be a one-argument function. eliminate no-longer-needed CVOID_TO_LISP. -- char/string macro changes: rename MAKE_CHAR() to make_emchar() for slightly less confusion with make_char(). (The former generates an Emchar, the latter a Lisp object. Conceivably we should rename make_char() -> wrap_char() and similarly for make_int(), make_float().) Similar changes for other *CHAR* macros -- we now consistently use names with `emchar' whenever we are working with Emchars. Any remaining name with just `char' always refers to a Lisp object. rename macros with XSTRING_* to string_* except for those that reference actual fields in the Lisp_String object, following conventions used elsewhere. rename set_string_{data,length} macros (the only ones to work with a Lisp_String_* instead of a Lisp_Object) to set_lispstringp_* to make the difference clear. try to be consistent about caps vs. lowercase in macro/inline-fun names for chars and such, which wasn't the case before. we now reserve caps either for XFOO_ macros that reference object fields (e.g. XSTRING_DATA) or for things that have non-function semantics, e.g. directly modifying an arg (BREAKUP_EMCHAR) or evaluating an arg (any arg) more than once. otherwise, use lowercase. here is a summary of most of the macros/inline funs changed by all of the above changes: BYTE_*_P -> byte_*_p XSTRING_BYTE -> string_byte set_string_data/length -> set_lispstringp_data/length XSTRING_CHAR_LENGTH -> string_char_length XSTRING_CHAR -> string_emchar INTBYTE_FIRST_BYTE_P -> intbyte_first_byte_p INTBYTE_LEADING_BYTE_P -> intbyte_leading_byte_p charptr_copy_char -> charptr_copy_emchar LEADING_BYTE_* -> leading_byte_* CHAR_* -> EMCHAR_* *_CHAR_* -> *_EMCHAR_* *_CHAR -> *_EMCHAR CHARSET_BY_ -> charset_by_* BYTE_SHIFT_JIS* -> byte_shift_jis* BYTE_BIG5* -> byte_big5* REP_BYTES_BY_FIRST_BYTE -> rep_bytes_by_first_byte char_to_unicode -> emchar_to_unicode valid_char_p -> valid_emchar_p Change intbyte_strcmp -> qxestrcmp_c (duplicated functionality). -- INTERFACE CHANGES AFFECTING LESS CODE: use DECLARE_INLINE_HEADER in various places. remove '#ifdef emacs' from XEmacs-only files. eliminate CHAR_TABLE_VALUE(), which duplicated the functionality of get_char_table(). add BUFFER_TEXT_LOOP to simplify iterations over buffer text. define typedefs for signed and unsigned types of fixed sizes (INT_32_BIT, UINT_32_BIT, etc.). create ALIGN_FOR_TYPE as a higher-level interface onto ALIGN_SIZE; fix code to use it. add charptr_emchar_len to return the text length of the character pointed to by a ptr; use it in place of charcount_to_bytecount(..., 1). add emchar_len to return the text length of a given character. add types Bytexpos and Charxpos to generalize Bytebpos/Bytecount and Charbpos/Charcount, in code (particularly, the extents code and redisplay code) that works with either kind of index. rename redisplay struct params with names such as `charbpos' to e.g. `charpos' when they are e.g. a Charxpos, not a Charbpos. eliminate xxDEFUN in place of DEFUN; no longer necessary with changes awhile back to doc.c. split up big ugly combined list of EXFUNs in lisp.h on a file-by-file basis, since other prototypes are similarly split. rewrite some "*_UNSAFE" macros as inline funs and eliminate the _UNSAFE suffix. move most string code from lisp.h to text.h; the string code and text.h code is now intertwined in such a fashion that they need to be in the same place and partially interleaved. (you can't create forward references for inline funs) automated/lisp-tests.el, automated/symbol-tests.el, automated/test-harness.el: Fix test harness to output FAIL messages to stderr when in batch mode. Fix up some problems in lisp-tests/symbol-tests that were causing spurious failures.
author ben
date Sun, 05 May 2002 11:33:57 +0000
parents abe6d1db359e
children 9a1950c1e051
line wrap: on
line source

;;; list-mode.el --- Major mode for buffers containing lists of items

;; Copyright (C) 1992-4, 1997 Free Software Foundation, Inc.
;; Copyright (C) 1996, 2000 Ben Wing.
 
;; Maintainer: XEmacs Development Team
;; Keywords: extensions, dumped

;; This file is part of XEmacs.

;; XEmacs is free software; you can redistribute it and/or modify it
;; under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; XEmacs is distributed in the hope that it will be useful, but
;; WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;; General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with XEmacs; see the file COPYING.  If not, write to the 
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Synched up with: Not synched

;;; Commentary:

;; This file is dumped with XEmacs.

;; Cleanup, merging with FSF by Ben Wing, January 1996

;;; Code:

(defvar list-mode-extent nil)
(make-variable-buffer-local 'list-mode-extent)

(defvar list-mode-map nil
  "Local map for buffers containing lists of items.")
(or list-mode-map
    (let ((map (setq list-mode-map (make-sparse-keymap 'list-mode-map))))
      (suppress-keymap map)
      (define-key map 'button2up 'list-mode-item-mouse-selected)
      (define-key map 'button2 'undefined)
      (define-key map "\C-m" 'list-mode-item-keyboard-selected)
;;
;; The following calls to `substitute-key-definition' losed because
;; they were based on an incorrect assumption that `forward-char' and
;; `backward-char' are bound to keys in the global map. This might not
;; be the case if a user binds motion keys to different functions,
;; and was not actually the case since 20.5 beta 28 or around.
;;
;;    (substitute-key-definition 'forward-char 'next-list-mode-item map
;;				 global-map)
;;    (substitute-key-definition 'backward-char 'previous-list-mode-item map
;;				 global-map)
;;
;; We bind standard keys to motion commands instead.
;;
      (dolist (key '(kp-right right (control ?f)))
	(define-key map key 'next-list-mode-item))
      (dolist (key '(kp-left left (control ?b)))
	(define-key map key 'previous-list-mode-item))))

;; #### We make list-mode-hook, as well as completion-setup-hook and
;; minibuffer-setup-hook, permanent-local so that it's possible to create
;; buffers in these modes and then set up some buffer-specific
;; customizations without resorting to awful kludges.  (The problem here
;; is that when you switch a buffer into a mode, reset-buffer is usually
;; called, which destroys all buffer-local settings that you carefully
;; tried to set up when you created the buffer.  Therefore, the only way
;; to set these variables is to use the setup hooks -- but if they are
;; not declared permanent local, then any local hook functions that you
;; put on them (which is exactly what you want to do) also get removed,
;; so you would have to resort to putting a global hook function on the
;; setup hook, and then making sure it gets removed later.  I actually
;; added some support for doing this with one-shot hooks, but this is
;; clearly not the correct way to do things, and it fails in some cases,
;; particularly when the buffer gets put into the mode more than once,
;; which typically happens with completion buffers, for example.)  In
;; fact, all setup hooks should be made permanent local, but I didn't
;; feel like making a global change like this quite yet.  The proper way
;; to do it would be to declare new def-style forms, such as defhook and
;; define-local-setup-hook, which are used to initialize hooks in place
;; of the current generic defvars. --ben

(put 'list-mode-hook 'permanent-local t)
(defvar list-mode-hook nil
  "Normal hook run when entering List mode.")

(defun list-mode ()
  "Major mode for buffer containing lists of items."
  (interactive)
  (kill-all-local-variables)
  (use-local-map list-mode-map)
  (setq mode-name "List")
  (setq major-mode 'list-mode)
  (add-local-hook 'post-command-hook 'set-list-mode-extent)
  (add-local-hook 'pre-command-hook 'list-mode-extent-pre-hook)
  (set (make-local-variable 'next-line-add-newlines) nil)
  (setq list-mode-extent nil)
;; It is visually disconcerting to have the text cursor disappear within list 
;; buffers, especially when moving from window to window, so leave it
;; visible.  -- Bob Weiner, 06/20/1999
; (set-specifier text-cursor-visible-p nil (current-buffer))
  (setq buffer-read-only t)
  (goto-char (point-min))
  (run-hooks 'list-mode-hook))

;; List mode is suitable only for specially formatted data.
(put 'list-mode 'mode-class 'special)

(defvar list-mode-extent-old-point nil
  "The value of point when pre-command-hook is called.
Used to determine the direction of motion.")
(make-variable-buffer-local 'list-mode-extent-old-point)

(defun list-mode-extent-pre-hook ()
  (setq list-mode-extent-old-point (point))
  ;(setq atomic-extent-goto-char-p nil)
)

(defun set-list-mode-extent ()
  "Move to the closest list item and set up the extent for it.
This is called from `post-command-hook'."
  (cond ((get-char-property (point) 'list-mode-item))
	((and (> (point) (point-min))
	      (get-char-property (1- (point)) 'list-mode-item))
	 (goto-char (1- (point))))
	(t
	 (let ((pos (point))
	       dirflag)
	   ;this fucks things up more than it helps.
	   ;atomic-extent-goto-char-p as currently defined is all broken,
	   ;since it will be triggered if the command *ever* runs goto-char!
	   ;(if atomic-extent-goto-char-p
	   ;    (setq dirflag 1)
	   (if (and list-mode-extent-old-point
		    (> pos list-mode-extent-old-point))
	       (setq dirflag 1)
	     (setq dirflag -1))
	   (next-list-mode-item dirflag)
	   (or (get-char-property (point) 'list-mode-item)
	       (next-list-mode-item (- dirflag))))))
  (or (and list-mode-extent
	   (eq (current-buffer) (extent-object list-mode-extent)))
      (progn
	(setq list-mode-extent (make-extent nil nil (current-buffer)))
	(set-extent-face list-mode-extent 'list-mode-item-selected)))
  (let ((ex (extent-at (point) nil 'list-mode-item nil 'at)))
    (if ex
	(progn
	  (set-extent-endpoints list-mode-extent
				(extent-start-position ex)
				(extent-end-position ex))
	  (auto-show-make-region-visible (extent-start-position ex)
					 (extent-end-position ex)))
      (detach-extent list-mode-extent))))

(defun previous-list-mode-item (n)
  "Move to the previous item in list-mode."
  (interactive "p")
  (next-list-mode-item (- n)))

(defun next-list-mode-item (n)
  "Move to the next item in list-mode.
With prefix argument N, move N items (negative N means move backward)."
  (interactive "p")
  (while (and (> n 0) (not (eobp)))
    (let ((extent (extent-at (point) (current-buffer) 'list-mode-item))
	  (end (point-max)))
      ;; If in a completion, move to the end of it.
      (if extent (goto-char (extent-end-position extent)))
      ;; Move to start of next one.
      (or (extent-at (point) (current-buffer) 'list-mode-item)
	  (goto-char (next-single-property-change (point) 'list-mode-item
						  nil end))))
    (setq n (1- n)))
  (while (and (< n 0) (not (bobp)))
    (let ((extent (extent-at (point) (current-buffer) 'list-mode-item))
	  (end (point-min)))
      ;; If in a completion, move to the start of it.
      (if extent (goto-char (extent-start-position extent)))
      ;; Move to the start of that one.
      (if (setq extent (extent-at (point) (current-buffer) 'list-mode-item
				  nil 'before))
	  (goto-char (extent-start-position extent))
	(goto-char (previous-single-property-change
		    (point) 'list-mode-item nil end))
	(if (setq extent (extent-at (point) (current-buffer) 'list-mode-item
				    nil 'before))
	    (goto-char (extent-start-position extent)))))
    (setq n (1+ n))))

(defun list-mode-item-selected-1 (extent event)
  (let ((func (extent-property extent 'list-mode-item-activate-callback))
	(user-data (extent-property extent 'list-mode-item-user-data)))
    (if func
	(funcall func event extent user-data))))

;; we could make these two be just one function, but we want to be
;; able to refer to them in DOC strings.

(defun list-mode-item-keyboard-selected ()
  (interactive)
  (list-mode-item-selected-1 (extent-at (point) (current-buffer)
					'list-mode-item nil 'at)
			     nil))

(defun list-mode-item-mouse-selected (event)
  (interactive "e")
  ;; Sometimes event-closest-point returns nil.
  ;; So beep instead of bombing.
  (let ((point (event-closest-point event)))
    (if point
	(list-mode-item-selected-1 (extent-at point
					      (event-buffer event)
					      'list-mode-item nil 'at)
				   event)
      (ding))))

(defun add-list-mode-item (start end &optional buffer activate-callback
				 user-data)
  "Add a new list item in list-mode, from START to END in BUFFER.
BUFFER defaults to the current buffer.
This works by creating an extent for the span of text in question.
If ACTIVATE-CALLBACK is non-nil, it should be a function of three
  arguments (EVENT EXTENT USER-DATA) that will be called when button2
  is pressed on the extent.  USER-DATA comes from the optional
  USER-DATA argument."
  (let ((extent (make-extent start end buffer)))
    (set-extent-property extent 'list-mode-item t)
    (set-extent-property extent 'start-open t)
    (if activate-callback
	(progn
	  (set-extent-property extent 'mouse-face 'highlight)
	  (set-extent-property extent 'list-mode-item-activate-callback
			       activate-callback)
	  (set-extent-property extent 'list-mode-item-user-data user-data)))
    extent))


;; Define the major mode for lists of completions.


(defvar completion-highlight-first-word-only nil
  "*Completion will only highlight the first blank delimited word if t.
If the variable in not t or nil, the string is taken as a regexp to match for end
of highlight")

;; see comment at list-mode-hook.
(put 'completion-setup-hook 'permanent-local t)
(defvar completion-setup-hook nil
  "Normal hook run at the end of setting up the text of a completion buffer.
When run, the completion buffer is the current buffer.")

; Unnecessary FSFmacs crock.  We frob the extents directly in
; display-completion-list, so no "heuristics" like this are necessary.
;(defvar completion-fixup-function nil
;  "A function to customize how completions are identified in completion lists.
;`completion-setup-function' calls this function with no arguments
;each time it has found what it thinks is one completion.
;Point is at the end of the completion in the completion list buffer.
;If this function moves point, it can alter the end of that completion.")

(defvar completion-default-help-string
  '(concat
    (if (device-on-window-system-p)
	(substitute-command-keys
	 "Click \\<list-mode-map>\\[list-mode-item-mouse-selected] on a completion to select it.\n") "")
    (substitute-command-keys
     "Type \\<minibuffer-local-completion-map>\\[advertised-switch-to-completions] or \\[switch-to-completions] to move to this buffer, for keyboard selection.\n\n"))
  "Form the evaluate to get a help string for completion lists.
This string is inserted at the beginning of the buffer.
See `display-completion-list'.")

(defun display-completion-list (completions &rest cl-keys)
  "Display the list of completions, COMPLETIONS, using `standard-output'.
Each element may be just a symbol or string or may be a list of two
 strings to be printed as if concatenated.
Frob a mousable extent onto each completion.  This extent has properties
 'mouse-face (so it highlights when the mouse passes over it) and
 'list-mode-item (so it can be located).

Keywords:
  :activate-callback (default is `default-choose-completion')
    See `add-list-mode-item'.
  :user-data
    Value passed to activation callback.
  :window-width
    If non-nil, width to use in displaying the list, instead of the
    actual window's width.
  :window-height
    If non-nil, use no more than this many lines, and extend line width as
    necessary.
  :help-string (default is the value of `completion-default-help-string')
    Form to evaluate to get a string to insert at the beginning of
    the completion list buffer.  This is evaluated when that buffer
    is the current buffer and after it has been put into
    completion-list-mode.
  :reference-buffer (default is the current buffer)
    This specifies the value of `completion-reference-buffer' in
    the completion buffer.  This specifies the buffer (normally a
    minibuffer) that `default-choose-completion' will insert the
    completion into.

At the end, run the normal hook `completion-setup-hook'.
It can find the completion buffer in `standard-output'.
If `completion-highlight-first-word-only' is non-nil, then only the start
 of the string is highlighted."
   ;; #### I18N3 should set standard-output to be (temporarily)
   ;; output-translating.
  (cl-parsing-keywords
      ((:activate-callback 'default-choose-completion)
       :user-data
       :reference-buffer
       (:help-string completion-default-help-string)
       (:completion-string "Possible completions are:")
       :window-width
       :window-height)
      ()
    (let ((old-buffer (current-buffer))
	  (bufferp (bufferp standard-output)))
      (if bufferp
	  (set-buffer standard-output))
      (if (null completions)
	  (princ (gettext
		  "There are no possible completions of what you have typed."))
	(let ((win-width
	       (or cl-window-width
		   (if bufferp
		       ;; This needs fixing for the case of windows 
		       ;; that aren't the same width's the frame.
		       ;; Sadly, the window it will appear in is not known
		       ;; until after the text has been made.

		       ;; We have to use last-nonminibuf-frame here
		       ;; and not selected-frame because if a
		       ;; minibuffer-only frame is being used it will
		       ;; be the selected-frame at the point this is
		       ;; run.  We keep the selected-frame call around
		       ;; just in case.
		       (frame-width (or (last-nonminibuf-frame)
					(selected-frame)))
		     80))))
	  (let ((count 0)
		(max-width 0)
		old-max-width)
	    ;; Find longest completion
	    (let ((tail completions))
	      (while tail
		(let* ((elt (car tail))
		       (len (cond ((stringp elt)
				   (length elt))
				  ((and (consp elt)
					(stringp (car elt))
					(stringp (car (cdr elt))))
				   (+ (length (car elt))
				      (length (car (cdr elt)))))
				  (t
				   (signal 'wrong-type-argument
					   (list 'stringp elt))))))
		  (if (> len max-width)
		      (setq max-width len))
		  (setq count (1+ count)
			tail (cdr tail)))))
        
	    (setq max-width (+ 2 max-width)) ; at least two chars between cols
	    (setq old-max-width max-width)
	    (let ((rows (let ((cols (min (/ win-width max-width) count)))
			  (if (<= cols 1)
			      count
			    (progn
			      ;; re-space the columns
			      (setq max-width (/ win-width cols))
			      (if (/= (% count cols) 0) ; want ceiling...
				  (1+ (/ count cols))
                                (/ count cols)))))))
	      (when
		  (and cl-window-height
		       (> rows cl-window-height))
		(setq max-width old-max-width)
		(setq rows cl-window-height))
	      (when (and (stringp cl-completion-string)
			 (> (length cl-completion-string) 0))
		(princ (gettext cl-completion-string))
		(terpri))
	      (let ((tail completions)
		    (r 0)
		    (regexp-string
		     (if (eq t
			     completion-highlight-first-word-only)
			 "[ \t]"
		       completion-highlight-first-word-only)))
		(while (< r rows)
		  (and (> r 0) (terpri))
		  (let ((indent 0)
			(column 0)
			(tail2 tail))
		    (while tail2
		      (let ((elt (car tail2)))
			(if (/= indent 0)
			    (if bufferp
				(indent-to indent 2)
                              (while (progn (write-char ?\ )
                                            (setq column (1+ column))
                                            (< column indent)))))
			(setq indent (+ indent max-width))
			(let ((start (point))
			      end)
			  ;; Frob some mousable extents in there too!
			  (if (consp elt)
			      (progn
				(princ (car elt))
				(princ (car (cdr elt)))
				(or bufferp
				    (setq column
					  (+ column
					     (length (car elt))
					     (length (car (cdr elt)))))))
			    (progn
			      (princ elt)
			      (or bufferp
				  (setq column (+ column (length
							  elt))))))
			  (add-list-mode-item
			   start
			   (progn
			     (setq end (point))
			     (or
			      (and completion-highlight-first-word-only
				   (goto-char start)
				   (re-search-forward regexp-string end t)
				   (match-beginning 0))
			      end))
			   nil cl-activate-callback cl-user-data)
			  (goto-char end)))
		      (setq tail2 (nthcdr rows tail2)))
		    (setq tail (cdr tail)
			  r (1+ r)))))))))
      (if bufferp
	  (set-buffer old-buffer)))
    (save-excursion
      (let ((mainbuf (or cl-reference-buffer (current-buffer))))
	(set-buffer standard-output)
	(completion-list-mode)
	(make-local-variable 'completion-reference-buffer)
	(setq completion-reference-buffer mainbuf)
;;; The value 0 is right in most cases, but not for file name completion.
;;; so this has to be turned off.
;;;      (setq completion-base-size 0)
	(goto-char (point-min))
	(let ((buffer-read-only nil))
	  (insert (eval cl-help-string)))
	  ;; unnecessary FSFmacs crock
	  ;;(forward-line 1)
	  ;;(while (re-search-forward "[^ \t\n]+\\( [^ \t\n]+\\)*" nil t)
	  ;;	  (let ((beg (match-beginning 0))
	  ;;		(end (point)))
	  ;;	    (if completion-fixup-function
	  ;;		(funcall completion-fixup-function))
	  ;;	    (put-text-property beg (point) 'mouse-face 'highlight)
	  ;;	    (put-text-property beg (point) 'list-mode-item t)
	  ;;	    (goto-char end)))))
	))
    (save-excursion
      (set-buffer standard-output)
      (run-hooks 'completion-setup-hook))))

(defvar completion-display-completion-list-function 'display-completion-list
  "Function to set up the list of completions in the completion buffer.
The function is called with one argument, the sorted list of completions.
Particular minibuffer interface functions (e.g. `read-file-name') may
want to change this.  To do that, set a local value for this variable
in the minibuffer; that ensures that other minibuffer invocations will
not be affected.")

(defun minibuffer-completion-help ()
  "Display a list of possible completions of the current minibuffer contents.
The list of completions is determined by calling `all-completions',
passing it the current minibuffer contents, the value of
`minibuffer-completion-table', and the value of
`minibuffer-completion-predicate'.  The list is displayed by calling
the value of `completion-display-completion-list-function' on the sorted
list of completions, with the standard output set to the completion
buffer."
  (interactive)
  (message "Making completion list...")
  (let ((completions (all-completions (buffer-string)
                                      minibuffer-completion-table
                                      minibuffer-completion-predicate)))
    (message nil)
    (if (null completions)
        (progn
          (ding nil 'no-completion)
          (temp-minibuffer-message " [No completions]"))
        (with-output-to-temp-buffer "*Completions*"
	  (funcall completion-display-completion-list-function
		   (sort completions #'string-lessp))))))

(define-derived-mode completion-list-mode list-mode 
  "Completion List"
  "Major mode for buffers showing lists of possible completions.
\\{completion-list-mode-map}"
  (make-local-variable 'completion-base-size)
  (setq completion-base-size nil))

(let ((map completion-list-mode-map))
  (define-key map 'button2up 'mouse-choose-completion)
  (define-key map 'button2 'undefined)
  (define-key map "\C-m" 'choose-completion)
  (define-key map "\e\e\e" 'delete-completion-window)
  (define-key map "\C-g" 'minibuffer-keyboard-quit)
  (define-key map "q" 'completion-list-mode-quit)
  (define-key map " " 'completion-switch-to-minibuffer)
  ;; [Tab] used to switch to the minibuffer but since [space] does that and
  ;; since most applications in the world use [Tab] to select the next item
  ;; in a list, do that in the *Completions* buffer too.  -- Bob Weiner,
  ;; BeOpen.com, 06/23/1999.
  (define-key map "\t" 'next-list-mode-item))

(defvar completion-reference-buffer nil
  "Record the buffer that was current when the completion list was requested.
This is a local variable in the completion list buffer.
Initial value is nil to avoid some compiler warnings.")

(defvar completion-base-size nil
  "Number of chars at beginning of minibuffer not involved in completion.
This is a local variable in the completion list buffer
but it talks about the buffer in `completion-reference-buffer'.
If this is nil, it means to compare text to determine which part
of the tail end of the buffer's text is involved in completion.")

;; These names are referenced in the doc string for `completion-list-mode'.
(defalias 'choose-completion 'list-mode-item-keyboard-selected)
(defalias 'mouse-choose-completion 'list-mode-item-mouse-selected)

(defun delete-completion-window ()
  "Delete the completion list window.
Go to the window from which completion was requested."
  (interactive)
  (let ((buf completion-reference-buffer))
    (delete-window (selected-window))
    (if (get-buffer-window buf)
	 (select-window (get-buffer-window buf)))))

(defun completion-switch-to-minibuffer ()
  "Move from a completions buffer to the active minibuffer window."
  (interactive)
  (select-window (minibuffer-window)))

(defun completion-list-mode-quit ()
  "Abort any recursive edit and bury the completions buffer."
  (interactive)
  (condition-case ()
      (abort-recursive-edit)
    (error nil))
  ;; If there was no recursive edit to abort, simply bury the completions
  ;; list buffer.
  (if (eq major-mode 'completion-list-mode) (bury-buffer)))

(defun completion-do-in-minibuffer ()
  (interactive "_")
  (save-excursion
    (set-buffer (window-buffer (minibuffer-window)))
    (call-interactively (key-binding (this-command-keys)))))

(defun default-choose-completion (event extent buffer)
  "Click on an alternative in the `*Completions*' buffer to choose it."
  (and (button-event-p event)
       ;; Give temporary modes such as isearch a chance to turn off.
       (run-hooks 'mouse-leave-buffer-hook))
  (or buffer (setq buffer (symbol-value-in-buffer
			   'completion-reference-buffer
			   (or (and (button-event-p event)
				    (event-buffer event))
			       (current-buffer)))))
  (save-selected-window
   (and (button-event-p event)
	(select-window (event-window event)))
   (if (and (one-window-p t 'selected-frame)
	    (window-dedicated-p (selected-window)))
       ;; This is a special buffer's frame
       (iconify-frame (selected-frame))
     (or (window-dedicated-p (selected-window))
	 (bury-buffer))))
  (choose-completion-string (extent-string extent)
			    buffer
			    completion-base-size))

;; Delete the longest partial match for STRING
;; that can be found before POINT.
(defun choose-completion-delete-max-match (string)
  (let ((len (min (length string)
		  (- (point) (point-min)))))
    (goto-char (- (point) (length string)))
    (if completion-ignore-case
	 (setq string (downcase string)))
    (while (and (> len 0)
		 (let ((tail (buffer-substring (point)
					       (+ (point) len))))
		   (if completion-ignore-case
		       (setq tail (downcase tail)))
		   (not (string= tail (substring string 0 len)))))
      (setq len (1- len))
      (forward-char 1))
    (delete-char len)))

;; Switch to BUFFER and insert the completion choice CHOICE.
;; BASE-SIZE, if non-nil, says how many characters of BUFFER's text
;; to keep.  If it is nil, use choose-completion-delete-max-match instead.
(defun choose-completion-string (choice &optional buffer base-size)
  (let ((buffer (or buffer completion-reference-buffer)))
    ;; If BUFFER is a minibuffer, barf unless it's the currently
    ;; active minibuffer.
    (if (and (string-match "\\` \\*Minibuf-[0-9]+\\*\\'" (buffer-name buffer))
	      (or (not (active-minibuffer-window))
		  (not (equal buffer
			      (window-buffer (active-minibuffer-window))))))
	 (error "Minibuffer is not active for completion")
      ;; Insert the completion into the buffer where completion was requested.
      (set-buffer buffer)
      (if base-size
	   (delete-region (+ base-size (point-min)) (point))
	 (choose-completion-delete-max-match choice))
      (insert choice)
      (remove-text-properties (- (point) (length choice)) (point)
			       '(highlight nil))
      ;; Update point in the window that BUFFER is showing in.
      (let ((window (get-buffer-window buffer t)))
	 (set-window-point window (point)))
      ;; If completing for the minibuffer, exit it with this choice.
      (and (equal buffer (window-buffer (minibuffer-window)))
	    minibuffer-completion-table
	    (exit-minibuffer)))))

(define-key minibuffer-local-completion-map [prior]
  'switch-to-completions)
(define-key minibuffer-local-must-match-map [prior]
  'switch-to-completions)
(define-key minibuffer-local-completion-map "\M-v"
  'advertised-switch-to-completions)
(define-key minibuffer-local-must-match-map "\M-v"
  'advertised-switch-to-completions)

(defalias 'advertised-switch-to-completions 'switch-to-completions)
(defun switch-to-completions ()
  "Select the completion list window."
  (interactive)
  ;; Make sure we have a completions window.
  (or (get-buffer-window "*Completions*")
      (minibuffer-completion-help))
  (if (not (get-buffer-window "*Completions*"))
      nil
    (select-window (get-buffer-window "*Completions*"))
    (goto-char (next-single-property-change (point-min) 'list-mode-item nil
					    (point-max)))))

;;; list-mode.el ends here