;; Avoid warning about delete-backward-char
(with-no-warnings (delete-backward-char n killp))))
-(defvar read-char-from-minibuffer-history nil
+(defvar read-char-history nil
"The default history for the `read-char-from-minibuffer' function.")
(defvar read-char-from-minibuffer-map
(let ((map (make-sparse-keymap)))
(set-keymap-parent map minibuffer-local-map)
(define-key map [remap self-insert-command]
- 'read-char-from-minibuffer-self-insert)
+ 'read-char-from-minibuffer-insert-char)
map)
"Keymap for the `read-char-from-minibuffer' function.")
-(defun read-char-from-minibuffer-self-insert ()
- "Insert the character you type in the minibuffer."
+(defconst read-char-from-minibuffer-map-hash
+ (make-hash-table :weakness 'key :test 'equal))
+
+(defun read-char-from-minibuffer-insert-char ()
+ "Insert the character you type in the minibuffer and exit.
+Discard all previous input before inserting and exiting the minibuffer."
(interactive)
(delete-minibuffer-contents)
- (insert (event-basic-type last-command-event))
+ (insert last-command-event)
(exit-minibuffer))
-(defun read-char-from-minibuffer (prompt)
- "Read a character from the minibuffer, prompting with string PROMPT.
-Like `read-char', but allows navigating in a history. The navigation
-commands are `M-p' and `M-n', with `RET' to select a character from
-history."
- (let ((result
- (read-from-minibuffer prompt nil
- read-char-from-minibuffer-map nil
- 'read-char-from-minibuffer-history)))
- (if (> (length result) 0)
- ;; We have a string (with one character), so return the first one.
- (elt result 0)
- ;; The default value is RET.
- (push "\r" read-char-from-minibuffer-history)
- ?\r)))
+(defun read-char-from-minibuffer-insert-other ()
+ "Handle inserting of a character other than allowed.
+Display an error on trying to insert a disallowed character.
+Also discard all previous input in the minibuffer."
+ (interactive)
+ (delete-minibuffer-contents)
+ (ding)
+ (minibuffer-message "Wrong answer")
+ (sit-for 2))
+
+(defvar empty-history)
+
+(defun read-char-from-minibuffer (prompt &optional chars history)
+ "Read a character from the minibuffer, prompting for PROMPT.
+Like `read-char', but uses the minibuffer to read and return a character.
+When CHARS is non-nil, any input that is not one of CHARS is ignored.
+When HISTORY is a symbol, then allows navigating in a history.
+The navigation commands are `M-p' and `M-n', with `RET' to select
+a character from history."
+ (discard-input)
+ (let* ((empty-history '())
+ (map (if (consp chars)
+ (or (gethash chars read-char-from-minibuffer-map-hash)
+ (puthash chars
+ (let ((map (make-sparse-keymap)))
+ (set-keymap-parent map read-char-from-minibuffer-map)
+ (dolist (char chars)
+ (define-key map (vector char)
+ 'read-char-from-minibuffer-insert-char))
+ (define-key map [remap self-insert-command]
+ 'read-char-from-minibuffer-insert-other)
+ map)
+ read-char-from-minibuffer-map-hash))
+ read-char-from-minibuffer-map))
+ (result
+ (read-from-minibuffer prompt nil map nil
+ (or history 'empty-history)))
+ (char
+ (if (> (length result) 0)
+ ;; We have a string (with one character), so return the first one.
+ (elt result 0)
+ ;; The default value is RET.
+ (when history (push "\r" (symbol-value history)))
+ ?\r)))
+ ;; Display the question with the answer.
+ (message "%s%s" prompt (char-to-string char))
+ char))
(defun zap-to-char (arg char)
"Kill up to and including ARGth occurrence of CHAR.
Case is ignored if `case-fold-search' is non-nil in the current buffer.
Goes backward if ARG is negative; error if CHAR not found."
(interactive (list (prefix-numeric-value current-prefix-arg)
- (read-char-from-minibuffer "Zap to char: ")))
+ (read-char-from-minibuffer "Zap to char: "
+ nil 'read-char-history)))
;; Avoid "obsolete" warnings for translation-table-for-input.
(with-no-warnings
(if (char-table-p translation-table-for-input)