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emacs/lisp/cus-theme.el
Lars Ingebrigtsen 344634d7cc Allow obsoleting themes
* lisp/cus-theme.el (customize-themes): Don't list obsolete themes.

* lisp/custom.el (load-theme): Issue a warning if the theme is
obsolete (bug#47047).
2021-10-03 11:04:04 +02:00

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;;; cus-theme.el --- custom theme creation user interface -*- lexical-binding: t -*-
;; Copyright (C) 2001-2021 Free Software Foundation, Inc.
;; Author: Alex Schroeder <alex@gnu.org>
;; Maintainer: emacs-devel@gnu.org
;; Keywords: help, faces
;; Package: emacs
;; 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:
(require 'widget)
(require 'cus-edit)
(eval-when-compile
(require 'wid-edit))
(defvar custom-new-theme-mode-map
(let ((map (make-keymap)))
(set-keymap-parent map (make-composed-keymap widget-keymap
special-mode-map))
(suppress-keymap map)
(define-key map "\C-x\C-s" 'custom-theme-write)
(define-key map "q" 'Custom-buffer-done)
(define-key map "n" 'widget-forward)
(define-key map "p" 'widget-backward)
map)
"Keymap for `custom-new-theme-mode'.")
(define-derived-mode custom-new-theme-mode nil "Custom-Theme"
"Major mode for editing Custom themes.
Do not call this mode function yourself. It is meant for internal use."
(use-local-map custom-new-theme-mode-map)
(custom--initialize-widget-variables)
(setq-local revert-buffer-function #'custom-theme-revert))
(put 'custom-new-theme-mode 'mode-class 'special)
(defvar custom-theme-name nil)
;; Each element has the form (VAR CHECKBOX-WIDGET VAR-WIDGET)
(defvar custom-theme-variables nil)
;; Each element has the form (FACE CHECKBOX-WIDGET FACE-WIDGET)
(defvar custom-theme-faces nil)
(defvar custom-theme-description nil)
(defvar custom-theme--migrate-settings nil)
(defvar custom-theme-insert-variable-marker nil)
(defvar custom-theme-insert-face-marker nil)
(defvar custom-theme--listed-faces '(default cursor fixed-pitch
variable-pitch escape-glyph homoglyph
minibuffer-prompt highlight region
shadow secondary-selection trailing-whitespace
font-lock-builtin-face font-lock-comment-delimiter-face
font-lock-comment-face font-lock-constant-face
font-lock-doc-face font-lock-doc-markup-face font-lock-function-name-face
font-lock-keyword-face font-lock-negation-char-face
font-lock-preprocessor-face font-lock-regexp-grouping-backslash
font-lock-regexp-grouping-construct font-lock-string-face
font-lock-type-face font-lock-variable-name-face
font-lock-warning-face button link link-visited fringe
header-line tooltip mode-line mode-line-buffer-id
mode-line-emphasis mode-line-highlight mode-line-inactive
isearch isearch-fail lazy-highlight match next-error
query-replace)
"Faces listed by default in the *Custom Theme* buffer.")
(defvar custom-theme--save-name)
;;;###autoload
(defun customize-create-theme (&optional theme buffer)
"Create or edit a custom theme.
THEME, if non-nil, should be an existing theme to edit. If THEME
is `user', the resulting *Custom Theme* buffer also contains a
checkbox for removing the theme settings specified in the buffer
from the Custom save file.
BUFFER, if non-nil, should be a buffer to use; the default is
named *Custom Theme*."
(interactive)
(switch-to-buffer (get-buffer-create (or buffer "*Custom Theme*")))
(let ((inhibit-read-only t))
(erase-buffer)
(delete-all-overlays))
(custom-new-theme-mode)
(make-local-variable 'custom-theme-name)
(setq-local custom-theme--save-name theme)
(setq-local custom-theme-faces nil)
(setq-local custom-theme-variables nil)
(setq-local custom-theme-description "")
(setq-local custom-theme--migrate-settings nil)
(make-local-variable 'custom-theme-insert-face-marker)
(make-local-variable 'custom-theme-insert-variable-marker)
(make-local-variable 'custom-theme--listed-faces)
(when (called-interactively-p 'interactive)
(unless (y-or-n-p "Include basic face customizations in this theme? ")
(setq custom-theme--listed-faces nil)))
(let (vars values faces face-specs)
;; Load the theme settings.
(when theme
(if (eq theme 'user)
(widget-insert "This buffer contains all the Custom settings you have made.
You can convert them into a new custom theme, and optionally
remove them from your saved Custom file.\n\n")
(load-theme theme nil t))
(dolist (setting (get theme 'theme-settings))
(if (eq (car setting) 'theme-value)
(progn (push (nth 1 setting) vars)
(push (nth 3 setting) values))
(push (nth 1 setting) faces)
(push (nth 3 setting) face-specs))))
(widget-create 'push-button
:tag " Visit Theme "
:help-echo "Insert the settings of a pre-defined theme."
:action (lambda (_widget &optional _event)
(call-interactively #'custom-theme-visit-theme)))
(widget-insert " ")
(widget-create 'push-button
:tag " Merge Theme "
:help-echo "Merge in the settings of a pre-defined theme."
:action (lambda (_widget &optional _event)
(call-interactively #'custom-theme-merge-theme)))
(widget-insert " ")
(widget-create 'push-button
:tag " Revert "
:help-echo "Revert this buffer to its original state."
:action (lambda (&rest ignored) (revert-buffer)))
(widget-insert "\n\nTheme name : ")
(setq custom-theme-name
(widget-create 'editable-field
:value (if (and theme (not (eq theme 'user)))
(symbol-name theme)
"")))
(widget-insert "Description: ")
(setq custom-theme-description
(widget-create 'text :format "%v"
:value (or (get theme 'theme-documentation)
(format-time-string "Created %Y-%m-%d."))))
(widget-create 'push-button
:notify #'custom-theme-write
" Save Theme ")
(when (eq theme 'user)
(setq custom-theme--migrate-settings t)
(widget-insert " ")
(widget-create 'checkbox
:value custom-theme--migrate-settings
:action (lambda (widget &optional event)
(when (widget-value widget)
(widget-toggle-action widget event)
(setq custom-theme--migrate-settings
(widget-value widget)))))
(widget-insert (propertize " Remove saved theme settings from Custom save file."
'face '(variable-pitch (:height 0.9)))))
;; If THEME is non-nil, insert all of that theme's faces.
;; Otherwise, insert those in `custom-theme--listed-faces'.
(widget-insert "\n\n Theme faces:\n ")
(if theme
(while faces
(custom-theme-add-face-1 (pop faces) (pop face-specs)))
(dolist (face custom-theme--listed-faces)
(custom-theme-add-face-1 face nil)))
(setq custom-theme-insert-face-marker (point-marker))
(widget-insert " ")
(widget-create 'push-button
:tag "Insert Additional Face"
:help-echo "Add another face to this theme."
:follow-link 'mouse-face
:button-face 'custom-link
:mouse-face 'highlight
:pressed-face 'highlight
:action (lambda (_widget &optional _event)
(call-interactively #'custom-theme-add-face)))
;; If THEME is non-nil, insert all of that theme's variables.
(widget-insert "\n\n Theme variables:\n ")
(if theme
(while vars
(if (eq (car vars) 'custom-enabled-themes)
(progn (pop vars) (pop values))
(custom-theme-add-var-1 (pop vars) (eval (pop values))))))
(setq custom-theme-insert-variable-marker (point-marker))
(widget-insert " ")
(widget-create 'push-button
:tag "Insert Variable"
:help-echo "Add another variable to this theme."
:follow-link 'mouse-face
:button-face 'custom-link
:mouse-face 'highlight
:pressed-face 'highlight
:action (lambda (_widget &optional _event)
(call-interactively #'custom-theme-add-variable)))
(widget-insert ?\n)
(widget-setup)
(goto-char (point-min))
(message "")))
(defun custom-theme-revert (_ignore-auto noconfirm)
"Revert the current *Custom Theme* buffer.
This is the `revert-buffer-function' for `custom-new-theme-mode'."
(when (or noconfirm (y-or-n-p "Discard current changes? "))
(customize-create-theme custom-theme--save-name (current-buffer))))
;;; Theme variables
(defun custom-theme-add-variable (var value)
"Add a widget for VAR (a symbol) to the *New Custom Theme* buffer.
VALUE should be a value to which to set the widget; when called
interactively, this defaults to the current value of VAR."
(interactive
(let ((v (read-variable "Variable name: ")))
(list v (symbol-value v))))
(let ((entry (assq var custom-theme-variables)))
(cond ((null entry)
;; If VAR is not yet in the buffer, add it.
(save-excursion
(goto-char custom-theme-insert-variable-marker)
(custom-theme-add-var-1 var value)
(move-marker custom-theme-insert-variable-marker (point))
(widget-setup)))
;; Otherwise, alter that var widget.
(t
(widget-value-set (nth 1 entry) t)
(let ((widget (nth 2 entry)))
(widget-put widget :shown-value (list value))
(custom-redraw widget))))))
(defun custom-theme-add-var-1 (symbol val)
(widget-insert " ")
(push (list symbol
(prog1 (widget-create 'checkbox
:value t
:help-echo "Enable/disable this variable.")
(widget-insert " "))
(widget-create 'custom-variable
:tag (custom-unlispify-tag-name symbol)
:value symbol
:shown-value (list val)
:notify #'ignore
:custom-level 0
:custom-state 'hidden
:custom-style 'simple))
custom-theme-variables)
(widget-insert " "))
;;; Theme faces
(defun custom-theme-add-face (face &optional spec)
"Add a widget for FACE (a symbol) to the *New Custom Theme* buffer.
SPEC, if non-nil, should be a face spec to which to set the widget."
(interactive (list (read-face-name "Face name" (face-at-point t))))
(unless (or (facep face) spec)
(error "`%s' has no face definition" face))
(let ((entry (assq face custom-theme-faces)))
(cond ((null entry)
;; If FACE is not yet in the buffer, add it.
(save-excursion
(goto-char custom-theme-insert-face-marker)
(custom-theme-add-face-1 face spec)
(move-marker custom-theme-insert-face-marker (point))
(widget-setup)))
;; Otherwise, if SPEC is supplied, alter that face widget.
(spec
(widget-value-set (nth 1 entry) t)
(let ((widget (nth 2 entry)))
(widget-put widget :shown-value spec)
(custom-redraw widget)))
((called-interactively-p 'interactive)
(error "`%s' is already present" face)))))
(defun custom-theme-add-face-1 (symbol spec)
(widget-insert " ")
(push (list symbol
(prog1
(widget-create 'checkbox
:value t
:help-echo "Enable/disable this face.")
(widget-insert " "))
(widget-create 'custom-face
:tag (custom-unlispify-tag-name symbol)
:documentation-shown t
:value symbol
:custom-state 'hidden
:custom-style 'simple
:shown-value spec
:sample-indent 34))
custom-theme-faces)
(widget-insert " "))
;;; Reading and writing
;;;###autoload
(defun custom-theme-visit-theme (theme)
"Set up a Custom buffer to edit custom theme THEME."
(interactive
(list
(intern (completing-read "Find custom theme: "
(mapcar #'symbol-name
(custom-available-themes))))))
(unless (custom-theme-name-valid-p theme)
(error "No valid theme named `%s'" theme))
(cond ((not (eq major-mode 'custom-new-theme-mode))
(customize-create-theme theme))
((y-or-n-p "Discard current changes? ")
(setq custom-theme--save-name theme)
(custom-theme-revert nil t))))
(defun custom-theme-merge-theme (theme)
"Merge the custom theme THEME's settings into the current buffer."
(interactive
(list
(intern (completing-read "Merge custom theme: "
(mapcar #'symbol-name
(custom-available-themes))))))
(unless (eq theme 'user)
(unless (custom-theme-name-valid-p theme)
(error "Invalid theme name `%s'" theme))
(load-theme theme nil t))
(let ((settings (reverse (get theme 'theme-settings))))
(dolist (setting settings)
(let ((option (eq (car setting) 'theme-value))
(name (nth 1 setting))
(value (nth 3 setting)))
(unless (and option
(memq name '(custom-enabled-themes
custom-safe-themes)))
(funcall (if option
#'custom-theme-add-variable
#'custom-theme-add-face)
name value)))))
theme)
;; From cus-edit.el
(defvar custom-reset-standard-faces-list)
(defvar custom-reset-standard-variables-list)
(defun custom-theme-write (&rest _ignore)
"Write the current custom theme to its theme file."
(interactive)
(let* ((name (widget-value custom-theme-name))
(doc (widget-value custom-theme-description))
(vars custom-theme-variables)
(faces custom-theme-faces)
filename)
(when (string-equal name "")
(setq name (read-from-minibuffer "Theme name: " (user-login-name)))
(widget-value-set custom-theme-name name))
(unless (custom-theme-name-valid-p (intern name))
(error "Custom themes cannot be named `%s'" name))
(setq filename (expand-file-name (concat name "-theme.el")
custom-theme-directory))
(and (file-exists-p filename)
(not (y-or-n-p (format "File %s exists. Overwrite? " filename)))
(error "Aborted"))
(with-temp-buffer
(emacs-lisp-mode)
(unless (file-directory-p custom-theme-directory)
(make-directory (file-name-as-directory custom-theme-directory) t))
(setq buffer-file-name filename)
(erase-buffer)
(insert "(deftheme " name)
(if doc (insert "\n \"" doc "\""))
(insert ")\n")
(custom-theme-write-variables name (reverse vars))
(custom-theme-write-faces name (reverse faces))
(insert "\n(provide-theme '" name ")\n")
(save-buffer))
(message "Theme written to %s" filename)
(when custom-theme--migrate-settings
;; Remove these settings from the Custom file.
(let ((custom-reset-standard-variables-list '(t))
(custom-reset-standard-faces-list '(t)))
(dolist (var vars)
(when (and (not (eq (car var) 'custom-enabled-themes))
(widget-get (nth 1 var) :value))
(widget-apply (nth 2 var) :custom-mark-to-reset-standard)))
(dolist (face faces)
(when (widget-get (nth 1 face) :value)
(widget-apply (nth 2 face) :custom-mark-to-reset-standard)))
(custom-save-all))
(let ((custom-theme-load-path (list 'custom-theme-directory)))
(load-theme (intern name))))))
(defun custom-theme-write-variables (theme vars)
"Write a `custom-theme-set-variables' command for THEME.
It includes all variables in list VARS."
(when vars
(let ((standard-output (current-buffer)))
(princ "\n(custom-theme-set-variables\n")
(princ " '")
(princ theme)
(princ "\n")
(dolist (spec vars)
(when (widget-get (nth 1 spec) :value)
(let* ((symbol (nth 0 spec))
(widget (nth 2 spec))
(child (car-safe (widget-get widget :children)))
(value (if child
(widget-value child)
;; Child is null if the widget is closed (hidden).
(car (widget-get widget :shown-value)))))
(unless (bolp)
(princ "\n"))
(princ " '(")
(prin1 symbol)
(princ " ")
(prin1 (custom-quote value))
(princ ")"))))
(if (bolp)
(princ " "))
(princ ")")
(when (/= (following-char) ?\n)
(princ "\n")))))
(defun custom-theme-write-faces (theme faces)
"Write a `custom-theme-set-faces' command for THEME.
It includes all faces in list FACES."
(when faces
(let ((standard-output (current-buffer)))
(princ "\n(custom-theme-set-faces\n")
(princ " '")
(princ theme)
(princ "\n")
(dolist (spec faces)
;; Insert the face iff the checkbox widget is checked.
(when (widget-get (nth 1 spec) :value)
(let* ((symbol (nth 0 spec))
(widget (nth 2 spec))
(value
(cond
((car-safe (widget-get widget :children))
(custom-face-widget-to-spec widget))
;; Child is null if the widget is closed (hidden).
((widget-get widget :shown-value))
(t (custom-face-get-current-spec symbol)))))
(when value
(princ (if (bolp) " '(" "\n '("))
(prin1 symbol)
(princ " ")
(prin1 value)
(princ ")")))))
(if (bolp) (princ " "))
(princ ")")
(when (/= (following-char) ?\n)
(princ "\n")))))
;;; Describing Custom themes.
;;;###autoload
(defun describe-theme (theme)
"Display a description of the Custom theme THEME (a symbol)."
(interactive
(list
(intern (completing-read "Describe custom theme: "
(mapcar #'symbol-name
(custom-available-themes))))))
(unless (custom-theme-name-valid-p theme)
(error "Invalid theme name `%s'" theme))
(help-setup-xref (list 'describe-theme theme)
(called-interactively-p 'interactive))
(with-help-window (help-buffer)
(with-current-buffer standard-output
(describe-theme-1 theme))))
(defun describe-theme-1 (theme)
(prin1 theme)
(princ " is a custom theme")
(let ((fn (locate-file (concat (symbol-name theme) "-theme.el")
(custom-theme--load-path)
'("" "c")))
doc)
(when fn
(princ (substitute-command-keys " in `"))
(help-insert-xref-button (file-name-nondirectory fn)
'help-theme-def fn)
(princ (substitute-command-keys "'")))
(princ ".\n")
(if (custom-theme-p theme)
(progn
(if (custom-theme-enabled-p theme)
(princ "It is loaded and enabled.")
(princ "It is loaded but disabled."))
(setq doc (get theme 'theme-documentation)))
(princ "It is not loaded.")
;; Attempt to grab the theme documentation
(when fn
(with-temp-buffer
(insert-file-contents fn)
(let ((sexp (let ((read-circle nil))
(condition-case nil
(read (current-buffer))
(end-of-file nil)))))
(and (eq (car-safe sexp) 'deftheme)
(setq doc (nth 2 sexp)))))))
(princ "\n\nDocumentation:\n")
(princ (if (stringp doc)
(substitute-command-keys doc)
"No documentation available.")))
(princ "\n\nYou can ")
(help-insert-xref-button "customize" 'help-theme-edit theme)
(princ " this theme."))
;;; Theme chooser
(defvar custom--listed-themes)
(defcustom custom-theme-allow-multiple-selections nil
"Whether to allow multi-selections in the *Custom Themes* buffer."
:version "24.1"
:type 'boolean
:group 'custom-buffer)
(defvar custom-theme-choose-mode-map
(let ((map (make-keymap)))
(set-keymap-parent map (make-composed-keymap widget-keymap
special-mode-map))
(suppress-keymap map)
(define-key map "\C-x\C-s" 'custom-theme-save)
(define-key map "n" 'widget-forward)
(define-key map "p" 'widget-backward)
(define-key map "?" 'custom-describe-theme)
map)
"Keymap for `custom-theme-choose-mode'.")
(define-derived-mode custom-theme-choose-mode special-mode "Themes"
"Major mode for selecting Custom themes.
Do not call this mode function yourself. It is meant for internal use."
(use-local-map custom-theme-choose-mode-map)
(custom--initialize-widget-variables)
(setq-local revert-buffer-function
(lambda (_ignore-auto noconfirm)
(when (or noconfirm (y-or-n-p "Discard current choices? "))
(customize-themes (current-buffer))))))
(put 'custom-theme-choose-mode 'mode-class 'special)
;;;###autoload
(defun customize-themes (&optional buffer)
"Display a selectable list of Custom themes.
When called from Lisp, BUFFER should be the buffer to use; if
omitted, a buffer named *Custom Themes* is used."
(interactive)
(switch-to-buffer (get-buffer-create (or buffer "*Custom Themes*")))
(let ((inhibit-read-only t))
(erase-buffer))
(custom-theme-choose-mode)
(setq-local custom--listed-themes nil)
(make-local-variable 'custom-theme-allow-multiple-selections)
(and (null custom-theme-allow-multiple-selections)
(> (length custom-enabled-themes) 1)
(setq custom-theme-allow-multiple-selections t))
(widget-insert
(substitute-command-keys
"Type RET or click to enable/disable listed custom themes.
Type \\[custom-describe-theme] to describe the theme at point.
Theme files are named *-theme.el in `"))
(widget-create 'link :value "custom-theme-load-path"
:button-face 'custom-link
:mouse-face 'highlight
:pressed-face 'highlight
:help-echo "Describe `custom-theme-load-path'."
:keymap custom-mode-link-map
:follow-link 'mouse-face
:action (lambda (_widget &rest _ignore)
(describe-variable 'custom-theme-load-path)))
(widget-insert (substitute-command-keys "'.\n\n"))
;; If the user has made customizations, display a warning and
;; provide buttons to disable or convert them.
(let ((user-settings (get 'user 'theme-settings)))
(unless (or (null user-settings)
(and (null (cdr user-settings))
(eq (caar user-settings) 'theme-value)
(eq (cadr (car user-settings)) 'custom-enabled-themes)))
(widget-insert
(propertize
" Note: Your custom settings take precedence over theme settings.
To migrate your settings into a theme, click "
'face 'font-lock-warning-face))
(widget-create 'link :value "here"
:button-face 'custom-link
:mouse-face 'highlight
:pressed-face 'highlight
:help-echo "Migrate."
:keymap custom-mode-link-map
:follow-link 'mouse-face
:action (lambda (_widget &rest _ignore)
(customize-create-theme 'user)))
(widget-insert ".\n\n")))
(widget-create 'push-button
:tag " Save Theme Settings "
:help-echo "Save the selected themes for future sessions."
:action #'custom-theme-save)
(widget-insert ?\n)
(widget-create 'checkbox
:value custom-theme-allow-multiple-selections
:action #'custom-theme-selections-toggle)
(widget-insert (propertize " Select more than one theme at a time"
'face '(variable-pitch (:height 0.9))))
(widget-insert "\n\nAvailable Custom Themes:\n")
(let ((help-echo "mouse-2: Enable this theme for this session")
widget)
(dolist (theme (custom-available-themes))
;; Don't list obsolete themes.
(unless (get theme 'byte-obsolete-info)
(setq widget (widget-create 'checkbox
:value (custom-theme-enabled-p theme)
:theme-name theme
:help-echo help-echo
:action #'custom-theme-checkbox-toggle))
(push (cons theme widget) custom--listed-themes)
(widget-create-child-and-convert widget 'push-button
:button-face-get 'ignore
:mouse-face-get 'ignore
:value (format " %s" theme)
:action #'widget-parent-action
:help-echo help-echo)
(widget-insert " -- "
(propertize (custom-theme-summary theme)
'face 'shadow)
?\n))))
(goto-char (point-min))
(widget-setup))
(defun custom-theme-summary (theme)
"Return the summary line of THEME."
(let (doc)
(if (custom-theme-p theme)
(setq doc (get theme 'theme-documentation))
(let ((fn (locate-file (concat (symbol-name theme) "-theme.el")
(custom-theme--load-path)
'("" "c"))))
(when fn
(with-temp-buffer
(insert-file-contents fn)
(let ((sexp (let ((read-circle nil))
(condition-case nil
(progn
(re-search-forward "^(deftheme")
(beginning-of-line)
(read (current-buffer)))
(error nil)))))
(setq doc (nth 2 sexp)))))))
(cond ((null doc)
"(no documentation available)")
((string-match ".*" doc)
(match-string 0 doc))
(t doc))))
(defun custom-theme-checkbox-toggle (widget &optional event)
(let ((this-theme (widget-get widget :theme-name)))
(if (widget-value widget)
;; Disable the theme.
(progn
(disable-theme this-theme)
(widget-toggle-action widget event))
;; Enable the theme.
(unless custom-theme-allow-multiple-selections
;; If only one theme is allowed, disable all other themes and
;; uncheck their boxes.
(dolist (theme custom-enabled-themes)
(and (not (eq theme this-theme))
(assq theme custom--listed-themes)
(disable-theme theme)))
(dolist (theme custom--listed-themes)
(unless (eq (car theme) this-theme)
(widget-value-set (cdr theme) nil)
(widget-apply (cdr theme) :notify (cdr theme) event))))
(when (load-theme this-theme)
(widget-toggle-action widget event)))
;; Mark `custom-enabled-themes' as "set for current session".
(put 'custom-enabled-themes 'customized-value
(list (custom-quote custom-enabled-themes)))))
(defun custom-describe-theme ()
"Describe the Custom theme on the current line."
(interactive)
(let ((widget (widget-at (line-beginning-position))))
(and widget
(describe-theme (widget-get widget :theme-name)))))
(defun custom-theme-save (&rest _ignore)
(interactive)
(customize-save-variable 'custom-enabled-themes custom-enabled-themes)
(message "Custom themes saved for future sessions."))
(defun custom-theme-selections-toggle (widget &optional event)
(when (widget-value widget)
;; Deactivate multiple-selections.
(if (< 1 (length (delq nil (mapcar (lambda (x) (widget-value (cdr x)))
custom--listed-themes))))
(error "More than one theme is currently selected")))
(widget-toggle-action widget event)
(setq custom-theme-allow-multiple-selections (widget-value widget)))
(provide 'cus-theme)
;;; cus-theme.el ends here