emacs/lisp/mb-depth.el

92 lines
3.4 KiB
EmacsLisp

;;; mb-depth.el --- Indicate minibuffer-depth in prompt -*- lexical-binding: t -*-
;;
;; Copyright (C) 2006-2024 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 <https://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; Defines the minor mode `minibuffer-depth-indicate-mode'.
;;
;; When active, any recursive use of the minibuffer will show
;; the recursion depth in the minibuffer prompt. This is only
;; useful if `enable-recursive-minibuffers' is non-nil.
;;; Code:
(defcustom minibuffer-depth-indicator-function nil
"If non-nil, a function to produce the minibuffer depth indicator.
The function will be called with one argument, the minibuffer depth,
and must return a string to display as indication of the minibuffer
depth.
If nil, display the depth as a number inside brackets, [NN], with
the `minibuffer-depth-indicator' face."
:version "28.1"
:type '(choice (const :tag "Default indicator display, [NN]" nil)
(function))
:group 'minibuffer)
(defface minibuffer-depth-indicator '((t :inherit highlight))
"Face to use for minibuffer depth indicator."
:group 'minibuffer
:version "28.1")
;; An overlay covering the prompt. This is a buffer-local variable in
;; each affected minibuffer.
;;
(defvar minibuffer-depth-overlay)
(make-variable-buffer-local 'minibuffer-depth-overlay)
;; This function goes on minibuffer-setup-hook
(defun minibuffer-depth-setup ()
"Set up a minibuffer for `minibuffer-depth-indicate-mode'.
The prompt should already have been inserted."
(let ((depth (minibuffer-depth)))
(when (> depth 1)
(let ((pos (point-min)))
(setq minibuffer-depth-overlay (make-overlay pos (1+ pos))))
(overlay-put minibuffer-depth-overlay 'before-string
(if minibuffer-depth-indicator-function
(funcall minibuffer-depth-indicator-function depth)
(concat (propertize (format "[%d]" depth)
'face
'minibuffer-depth-indicator)
" ")))
(overlay-put minibuffer-depth-overlay 'evaporate t))))
;;;###autoload
(define-minor-mode minibuffer-depth-indicate-mode
"Toggle Minibuffer Depth Indication mode.
Minibuffer Depth Indication mode is a global minor mode. When
enabled, any recursive use of the minibuffer will show the
recursion depth in the minibuffer prompt. This is only useful if
`enable-recursive-minibuffers' is non-nil."
:global t
:group 'minibuffer
(if minibuffer-depth-indicate-mode
;; Enable the mode
(add-hook 'minibuffer-setup-hook 'minibuffer-depth-setup)
;; Disable the mode
(remove-hook 'minibuffer-setup-hook 'minibuffer-depth-setup)))
(provide 'mb-depth)
;;; mb-depth.el ends here