emacs/lisp/emacs-lisp/rmc.el
Po Lu ecf08f0621 Merge from savannah/emacs-29
dc4e6b1329 ; Update copyright years in more files
64b3777631 ; Run set-copyright from admin.el
8e1c56ae46 ; Add 2024 to copyright years

# Conflicts:
#	doc/misc/modus-themes.org
#	doc/misc/texinfo.tex
#	etc/NEWS
#	etc/refcards/ru-refcard.tex
#	etc/themes/modus-operandi-theme.el
#	etc/themes/modus-themes.el
#	etc/themes/modus-vivendi-theme.el
#	lib/alloca.in.h
#	lib/binary-io.h
#	lib/c-ctype.h
#	lib/c-strcasecmp.c
#	lib/c-strncasecmp.c
#	lib/careadlinkat.c
#	lib/cloexec.c
#	lib/close-stream.c
#	lib/diffseq.h
#	lib/dup2.c
#	lib/filemode.h
#	lib/fpending.c
#	lib/fpending.h
#	lib/fsusage.c
#	lib/getgroups.c
#	lib/getloadavg.c
#	lib/gettext.h
#	lib/gettime.c
#	lib/gettimeofday.c
#	lib/group-member.c
#	lib/malloc.c
#	lib/md5-stream.c
#	lib/md5.c
#	lib/md5.h
#	lib/memmem.c
#	lib/memrchr.c
#	lib/nanosleep.c
#	lib/save-cwd.h
#	lib/sha1.c
#	lib/sig2str.c
#	lib/stdlib.in.h
#	lib/strtoimax.c
#	lib/strtol.c
#	lib/strtoll.c
#	lib/time_r.c
#	lib/xalloc-oversized.h
#	lisp/auth-source-pass.el
#	lisp/emacs-lisp/lisp-mnt.el
#	lisp/emacs-lisp/timer.el
#	lisp/info-look.el
#	lisp/jit-lock.el
#	lisp/loadhist.el
#	lisp/mail/rmail.el
#	lisp/net/ntlm.el
#	lisp/net/webjump.el
#	lisp/progmodes/asm-mode.el
#	lisp/progmodes/project.el
#	lisp/progmodes/sh-script.el
#	lisp/textmodes/flyspell.el
#	lisp/textmodes/reftex-toc.el
#	lisp/textmodes/reftex.el
#	lisp/textmodes/tex-mode.el
#	lisp/url/url-gw.el
#	m4/alloca.m4
#	m4/clock_time.m4
#	m4/d-type.m4
#	m4/dirent_h.m4
#	m4/dup2.m4
#	m4/euidaccess.m4
#	m4/fchmodat.m4
#	m4/filemode.m4
#	m4/fsusage.m4
#	m4/getgroups.m4
#	m4/getloadavg.m4
#	m4/getrandom.m4
#	m4/gettime.m4
#	m4/gettimeofday.m4
#	m4/gnulib-common.m4
#	m4/group-member.m4
#	m4/inttypes.m4
#	m4/malloc.m4
#	m4/manywarnings.m4
#	m4/mempcpy.m4
#	m4/memrchr.m4
#	m4/mkostemp.m4
#	m4/mktime.m4
#	m4/nproc.m4
#	m4/nstrftime.m4
#	m4/pathmax.m4
#	m4/pipe2.m4
#	m4/pselect.m4
#	m4/pthread_sigmask.m4
#	m4/readlink.m4
#	m4/realloc.m4
#	m4/sig2str.m4
#	m4/ssize_t.m4
#	m4/stat-time.m4
#	m4/stddef_h.m4
#	m4/stdint.m4
#	m4/stdio_h.m4
#	m4/stdlib_h.m4
#	m4/stpcpy.m4
#	m4/strnlen.m4
#	m4/strtoimax.m4
#	m4/strtoll.m4
#	m4/time_h.m4
#	m4/timegm.m4
#	m4/timer_time.m4
#	m4/timespec.m4
#	m4/unistd_h.m4
#	m4/warnings.m4
#	nt/configure.bat
#	nt/preprep.c
#	test/lisp/register-tests.el
2024-01-02 10:28:14 +08:00

270 lines
11 KiB
EmacsLisp

;;; rmc.el --- read from a multiple choice question -*- lexical-binding: t -*-
;; Copyright (C) 2016-2024 Free Software Foundation, Inc.
;; Maintainer: emacs-devel@gnu.org
;; 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 <https://www.gnu.org/licenses/>.
;;; Commentary:
;;; Code:
(defun rmc--add-key-description (elem)
(let* ((char (car elem))
(name (cadr elem))
(pos (seq-position name char))
(desc (key-description (char-to-string char)))
(graphical-terminal
(display-supports-face-attributes-p
'(:underline t) (window-frame)))
(altered-name
(cond
;; Not in the name string, or a special character.
((or (not pos)
(member desc '("ESC" "TAB" "RET" "DEL" "SPC")))
(format "%s %s"
(if graphical-terminal
(propertize desc 'face 'read-multiple-choice-face)
(propertize desc 'face 'help-key-binding))
name))
;; The prompt character is in the name, so highlight
;; it on graphical terminals.
(graphical-terminal
(setq name (copy-sequence name))
(put-text-property pos (1+ pos)
'face 'read-multiple-choice-face
name)
name)
;; And put it in [bracket] on non-graphical terminals.
(t
(concat
(substring name 0 pos)
"["
(upcase (substring name pos (1+ pos)))
"]"
(substring name (1+ pos)))))))
(cons char altered-name)))
(defun rmc--show-help (prompt help-string show-help choices altered-names)
(let* ((buf-name (if (stringp show-help)
show-help
"*Multiple Choice Help*"))
(buf (get-buffer-create buf-name)))
(if (stringp help-string)
(with-help-window buf
(with-current-buffer buf
(insert help-string)))
(with-help-window buf
(with-current-buffer buf
(erase-buffer)
(pop-to-buffer buf)
(insert prompt "\n\n")
(let* ((columns (/ (window-width) 25))
(fill-column 21)
(times 0)
(start (point)))
(dolist (elem choices)
(goto-char start)
(unless (zerop times)
(if (zerop (mod times columns))
;; Go to the next "line".
(goto-char (setq start (point-max)))
;; Add padding.
(while (not (eobp))
(end-of-line)
(insert (make-string (max (- (* (mod times columns)
(+ fill-column 4))
(current-column))
0)
?\s))
(forward-line 1))))
(setq times (1+ times))
(let ((text
(with-temp-buffer
(insert (format
"%c: %s\n"
(car elem)
(cdr (assq (car elem) altered-names))))
(fill-region (point-min) (point-max))
(when (nth 2 elem)
(let ((start (point)))
(insert (nth 2 elem))
(unless (bolp)
(insert "\n"))
(fill-region start (point-max))))
(buffer-string))))
(goto-char start)
(dolist (line (split-string text "\n"))
(end-of-line)
(if (not (bolp))
(insert line)
(insert (make-string
(max (- (* (mod (1- times) columns)
(+ fill-column 4))
(current-column))
0)
?\s))
(insert line "\n"))
(forward-line 1))))))))
buf))
;;;###autoload
(defun read-multiple-choice (prompt choices &optional help-string show-help
long-form)
"Ask user to select an entry from CHOICES, prompting with PROMPT.
This function is used to ask the user a question with multiple
choices.
CHOICES should be a list of the form (KEY NAME [DESCRIPTION]).
KEY is a character the user should type to select the entry.
NAME is a short name for the entry to be displayed while prompting
\(if there's no room, it might be shortened).
DESCRIPTION is an optional longer description of the entry; it will
be displayed in a help buffer if the user requests more help. This
help description has a fixed format in columns. For greater
flexibility, instead of passing a DESCRIPTION, the caller can pass
the optional argument HELP-STRING. This argument is a string that
should contain a more detailed description of all of the possible
choices. `read-multiple-choice' will display that description in a
help buffer if the user requests that.
If optional argument SHOW-HELP is non-nil, show the help screen
immediately, before any user input. If SHOW-HELP is a string,
use it as the name of the help buffer.
This function translates user input into responses by consulting
the bindings in `query-replace-map'; see the documentation of
that variable for more information. The relevant bindings for the
purposes of this function are `recenter', `scroll-up', `scroll-down',
and `edit'.
If the user types the `recenter', `scroll-up', or `scroll-down'
responses, the function performs the requested window recentering or
scrolling, and then asks the question again. If the user enters `edit',
the function starts a recursive edit. When the user exit the recursive
edit, the multiple-choice prompt gains focus again.
When `use-dialog-box' is t (the default), and the command using this
function was invoked via the mouse, this function pops up a GUI dialog
to collect the user input, but only if Emacs is capable of using GUI
dialogs. Otherwise, the function will always use text-mode dialogs.
The return value is the matching entry from the CHOICES list.
If LONG-FORM is non-nil, do a `completing-read' over the NAME elements
in CHOICES instead. In this case, GUI dialog is not used, regardless
of the value of `use-dialog-box' and whether the function was invoked
via a mouse gesture.
Usage example:
\(read-multiple-choice \"Continue connecting?\"
\\='((?a \"always\")
(?s \"session only\")
(?n \"no\")))"
(if long-form
(read-multiple-choice--long-answers prompt choices)
(read-multiple-choice--short-answers
prompt choices help-string show-help)))
(defun read-multiple-choice--short-answers (prompt choices help-string show-help)
(let* ((dialog-p (use-dialog-box-p))
(prompt-choices
(if (or show-help dialog-p) choices (append choices '((?? "?")))))
(altered-names (mapcar #'rmc--add-key-description prompt-choices))
(full-prompt
(format
"%s (%s): "
prompt
(mapconcat (lambda (e) (cdr e)) altered-names ", ")))
tchar buf wrong-char answer)
(save-window-excursion
(save-excursion
(if show-help
(setq buf (rmc--show-help prompt help-string show-help
choices altered-names)))
(while (not tchar)
(unless dialog-p
(message "%s%s"
(if wrong-char
"Invalid choice. "
"")
full-prompt))
(setq tchar
(if dialog-p
(x-popup-dialog
t
(cons prompt
(mapcar
(lambda (elem)
(cons (capitalize (cadr elem))
(car elem)))
prompt-choices)))
(condition-case nil
(let ((cursor-in-echo-area t))
(read-event))
(error nil))))
(setq answer (lookup-key query-replace-map (vector tchar) t))
(setq tchar
(cond
((eq answer 'recenter)
(recenter) t)
((eq answer 'scroll-up)
(ignore-errors (scroll-up-command)) t)
((eq answer 'scroll-down)
(ignore-errors (scroll-down-command)) t)
((eq answer 'scroll-other-window)
(ignore-errors (scroll-other-window)) t)
((eq answer 'scroll-other-window-down)
(ignore-errors (scroll-other-window-down)) t)
((eq answer 'edit)
(save-match-data
(save-excursion
(message "%s"
(substitute-command-keys
"Recursive edit; type \\[exit-recursive-edit] to return to help screen"))
(recursive-edit))))
(t tchar)))
(when (eq tchar t)
(setq wrong-char nil
tchar nil))
;; The user has entered an invalid choice, so display the
;; help messages.
(when (and (not (eq tchar nil))
(not (assq tchar choices)))
(setq wrong-char (not (memq tchar `(?? ,help-char)))
tchar nil)
(when wrong-char
(ding))
(setq buf (rmc--show-help prompt help-string show-help
choices altered-names))))))
(when (buffer-live-p buf)
(kill-buffer buf))
(assq tchar choices)))
(defun read-multiple-choice--long-answers (prompt choices)
(let ((answer
(completing-read
(concat prompt " ("
(mapconcat #'identity (mapcar #'cadr choices) "/")
") ")
(mapcar #'cadr choices) nil t)))
(seq-find (lambda (elem)
(equal (cadr elem) answer))
choices)))
(provide 'rmc)
;;; rmc.el ends here