diff options
Diffstat (limited to 'lisp/simple.el')
| -rw-r--r-- | lisp/simple.el | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/lisp/simple.el b/lisp/simple.el index cd4df60e394..49108025a40 100644 --- a/lisp/simple.el +++ b/lisp/simple.el @@ -636,6 +636,67 @@ column specified by the function `current-left-margin'." (delete-horizontal-space t)) (indent-according-to-mode))) +(defcustom read-quoted-char-radix 8 + "*Radix for \\[quoted-insert] and other uses of `read-quoted-char'. +Legitimate radix values are 8, 10 and 16." + :type '(choice (const 8) (const 10) (const 16)) + :group 'editing-basics) + +(defun read-quoted-char (&optional prompt) + "Like `read-char', but do not allow quitting. +Also, if the first character read is an octal digit, +we read any number of octal digits and return the +specified character code. Any nondigit terminates the sequence. +If the terminator is RET, it is discarded; +any other terminator is used itself as input. + +The optional argument PROMPT specifies a string to use to prompt the user. +The variable `read-quoted-char-radix' controls which radix to use +for numeric input." + (let ((message-log-max nil) done (first t) (code 0) translated) + (while (not done) + (let ((inhibit-quit first) + ;; Don't let C-h get the help message--only help function keys. + (help-char nil) + (help-form + "Type the special character you want to use, +or the octal character code. +RET terminates the character code and is discarded; +any other non-digit terminates the character code and is then used as input.")) + (setq translated (read-key (and prompt (format "%s-" prompt)))) + (if inhibit-quit (setq quit-flag nil))) + (if (integerp translated) + (setq translated (char-resolve-modifiers translated))) + (cond ((null translated)) + ((not (integerp translated)) + (setq unread-command-events + (listify-key-sequence (this-single-command-raw-keys)) + done t)) + ((/= (logand translated ?\M-\^@) 0) + ;; Turn a meta-character into a character with the 0200 bit set. + (setq code (logior (logand translated (lognot ?\M-\^@)) 128) + done t)) + ((and (<= ?0 translated) + (< translated (+ ?0 (min 10 read-quoted-char-radix)))) + (setq code (+ (* code read-quoted-char-radix) (- translated ?0))) + (and prompt (setq prompt (message "%s %c" prompt translated)))) + ((and (<= ?a (downcase translated)) + (< (downcase translated) + (+ ?a -10 (min 36 read-quoted-char-radix)))) + (setq code (+ (* code read-quoted-char-radix) + (+ 10 (- (downcase translated) ?a)))) + (and prompt (setq prompt (message "%s %c" prompt translated)))) + ((and (not first) (eq translated ?\C-m)) + (setq done t)) + ((not first) + (setq unread-command-events + (listify-key-sequence (this-single-command-raw-keys)) + done t)) + (t (setq code translated + done t))) + (setq first nil)) + code)) + (defun quoted-insert (arg) "Read next input character and insert it. This is useful for inserting control characters. |