1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
;;; minibuf-eldef.el --- Only show defaults in prompts when applicable
;;
;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
;; 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
;;
;; Author: Miles Bader <miles@gnu.org>
;; Keywords: convenience
;; This file is part of GNU Emacs.
;; GNU Emacs 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 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs 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 GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; Defines the mode `minibuffer-electric-default-mode'.
;;
;; When active, minibuffer prompts that show a default value only show
;; the default when it's applicable -- that is, when hitting RET would
;; yield the default value. If the user modifies the input such that
;; hitting RET would enter a non-default value, the prompt is modified
;; to remove the default indication (which is restored if the input is
;; ever restore to the match the initial input).
;;; Code:
(defvar minibuffer-default-in-prompt-regexps
'(("\\( (default\\>.*)\\):? \\'" . 1) ("\\( \\[.*\\]\\):? *\\'" . 1))
"*A list of regexps matching the parts of minibuffer prompts showing defaults.
When `minibuffer-electric-default-mode' is active, these regexps are
used to identify the portions of prompts to elide.
Each entry is either a string, which should be a regexp matching the
default portion of the prompt, or a cons cell, who's car is a regexp
matching the default part of the prompt, and who's cdr indicates the
regexp subexpression that matched.")
;;; Internal variables
;; A list of minibuffers to which we've added a post-command-hook.
(defvar minibuf-eldef-frobbed-minibufs nil)
;;; The following are all local variables in the minibuffer
;; Input pre-inserted into the minibuffer before the user can edit it.
(defvar minibuf-eldef-initial-input)
(make-variable-buffer-local 'minibuf-eldef-initial-input)
;; and the length of the buffer with it inserted.
(defvar minibuf-eldef-initial-buffer-length)
(make-variable-buffer-local 'minibuf-eldef-initial-buffer-length)
;; True if the current minibuffer prompt contains the default spec.
(defvar minibuf-eldef-showing-default-in-prompt)
(make-variable-buffer-local 'minibuf-eldef-showing-default-in-prompt)
;; An overlay covering the default portion of the prompt
(defvar minibuf-eldef-overlay)
(make-variable-buffer-local 'minibuf-eldef-overlay)
;;; Hook functions
;; This function goes on minibuffer-setup-hook
(defun minibuf-eldef-setup-minibuffer ()
"Set up a minibuffer for `minibuffer-electric-default-mode'.
The prompt and initial input should already have been inserted."
(let ((regexps minibuffer-default-in-prompt-regexps)
(match nil)
(inhibit-point-motion-hooks t))
(save-excursion
(save-restriction
;; Narrow to only the prompt
(goto-char (point-min))
(narrow-to-region (point) (minibuffer-prompt-end))
;; See the prompt contains a default input indicator
(while regexps
(setq match (pop regexps))
(if (re-search-forward (if (stringp match) match (car match)) nil t)
(setq regexps nil)
(setq match nil)))))
(if (not match)
;; Nope, so just make sure our post-command-hook isn't left around.
(remove-hook 'post-command-hook #'minibuf-eldef-update-minibuffer t)
;; Yup; set things up so we can frob the prompt as the state of
;; the input string changes.
(setq match (if (consp match) (cdr match) 0))
(setq minibuf-eldef-overlay
(make-overlay (match-beginning match) (match-end match)))
(setq minibuf-eldef-showing-default-in-prompt t)
(setq minibuf-eldef-initial-input
(minibuffer-contents-no-properties))
(setq minibuf-eldef-initial-buffer-length (point-max))
(add-to-list 'minibuf-eldef-frobbed-minibufs (current-buffer))
(add-hook 'post-command-hook #'minibuf-eldef-update-minibuffer nil t))))
;; post-command-hook to swap prompts when necessary
(defun minibuf-eldef-update-minibuffer ()
"Update a minibuffer's prompt to include a default only when applicable.
This is intended to be used as a minibuffer post-command-hook for
`minibuffer-electric-default-mode'; the minibuffer should have already
been set up by `minibuf-eldef-setup-minibuffer'."
(unless (eq minibuf-eldef-showing-default-in-prompt
(and (= (point-max) minibuf-eldef-initial-buffer-length)
(string-equal (minibuffer-contents-no-properties)
minibuf-eldef-initial-input)))
;; swap state
(setq minibuf-eldef-showing-default-in-prompt
(not minibuf-eldef-showing-default-in-prompt))
(cond (minibuf-eldef-showing-default-in-prompt
(overlay-put minibuf-eldef-overlay 'invisible nil)
(overlay-put minibuf-eldef-overlay 'intangible nil))
(t
(overlay-put minibuf-eldef-overlay 'invisible t)
(overlay-put minibuf-eldef-overlay 'intangible t)))))
;;; Note this definition must be at the end of the file, because
;;; `define-minor-mode' actually calls the mode-function if the
;;; associated variable is non-nil, which requires that all needed
;;; functions be already defined. [This is arguably a bug in d-m-m]
;;;###autoload
(define-minor-mode minibuffer-electric-default-mode
"Toggle Minibuffer Electric Default mode.
When active, minibuffer prompts that show a default value only show the
default when it's applicable -- that is, when hitting RET would yield
the default value. If the user modifies the input such that hitting RET
would enter a non-default value, the prompt is modified to remove the
default indication.
With prefix argument ARG, turn on if positive, otherwise off.
Returns non-nil if the new state is enabled."
:global t
:group 'minibuffer
(if minibuffer-electric-default-mode
;; Enable the mode
(add-hook 'minibuffer-setup-hook 'minibuf-eldef-setup-minibuffer)
;; Disable the mode
(remove-hook 'minibuffer-setup-hook 'minibuf-eldef-setup-minibuffer)
;; Remove our entry from any post-command-hook variable's it's still in
(dolist (minibuf minibuf-eldef-frobbed-minibufs)
(with-current-buffer minibuf
(remove-hook 'post-command-hook #'minibuf-eldef-update-minibuffer t)))
(setq minibuf-eldef-frobbed-minibufs nil)))
(provide 'minibuf-eldef)
;; arch-tag: 7e421fae-c275-4729-b0da-7836af377d3d
;;; minibuf-eldef.el ends here
|
