;;; thingatpt.el --- Get the `thing' at point
-;; Copyright (C) 1991,1992,1993 Free Software Foundation, Inc.
+;; Copyright (C) 1991,92,93,94,95,1996 Free Software Foundation, Inc.
;; Author: Mike Williams <mikew@gopher.dosli.govt.nz>
;; Keywords: extensions, matching, mouse
;; Created: Thu Mar 28 13:48:23 1991
-;; Version: $Revision: 1.1 $
;; This file is part of GNU Emacs.
;; GNU General Public License for more details.
;;; Commentary:
-;;
-;; This file provides routines for getting the `thing' at the location of
-;; point, whatever that `thing' happens to be. The `thing' is defined by
-;; it's beginning and end positions in the buffer.
+
+;; This file provides routines for getting the "thing" at the location of
+;; point, whatever that "thing" happens to be. The "thing" is defined by
+;; its beginning and end positions in the buffer.
;;
;; The function bounds-of-thing-at-point finds the beginning and end
-;; positions by moving first forward to the end of the `thing', and then
+;; positions by moving first forward to the end of the "thing", and then
;; backwards to the beginning. By default, it uses the corresponding
-;; forward-`thing' operator (eg. forward-word, forward-line).
+;; forward-"thing" operator (eg. forward-word, forward-line).
;;
;; Special cases are allowed for using properties associated with the named
-;; `thing':
+;; "thing":
;;
-;; forward-op Function to call to skip forward over a `thing' (or
+;; forward-op Function to call to skip forward over a "thing" (or
;; with a negative argument, backward).
;;
-;; beginning-op Function to call to skip to the beginning of a `thing'.
-;; end-op Function to call to skip to the end of a `thing'.
+;; beginning-op Function to call to skip to the beginning of a "thing".
+;; end-op Function to call to skip to the end of a "thing".
;;
;; Reliance on existing operators means that many `things' can be accessed
;; without further code: eg.
(provide 'thingatpt)
-;;=== Version =============================================================
-
-(defconst thing@pt-version (substring "$Revision: 1.1 $" 11 -2)
- "The revision number of thing@pt (as string). The complete RCS id is:
-
- $Id: thingatpt.el,v 1.1 1993/11/08 14:27:42 rms Exp rms $")
-
-;;=== Basic movement ======================================================
+;; Basic movement
;;;###autoload
-(defun forward-thing (THING &optional N)
+(defun forward-thing (thing &optional n)
"Move forward to the end of the next THING."
- (let ((forward-op (or (get THING 'forward-op)
- (intern-soft (format "forward-%s" THING)))))
+ (let ((forward-op (or (get thing 'forward-op)
+ (intern-soft (format "forward-%s" thing)))))
(if (fboundp forward-op)
- (funcall forward-op (or N 1))
- (error "Can't determine how to move over %ss" THING))))
+ (funcall forward-op (or n 1))
+ (error "Can't determine how to move over a %s" thing))))
-;;=== General routines ====================================================
+;; General routines
;;;###autoload
-(defun bounds-of-thing-at-point (THING)
- "Determine the start and end buffer locations for the THING at point,
-where THING is an entity for which there is a either a corresponding
-forward-THING operation, or corresponding beginning-of-THING and
-end-of-THING operations, eg. 'word, 'sentence, 'defun.
- Return a cons cell '(start . end) giving the start and end positions."
+(defun bounds-of-thing-at-point (thing)
+ "Determine the start and end buffer locations for the THING at point.
+THING is a symbol which specifies the kind of syntactic entity you want.
+Possibilities include `symbol', `list', `sexp', `defun', `filename', `url',
+`word', `sentence', `whitespace', `line', `page' and others.
+
+See the file `thingatpt.el' for documentation on how to define
+a symbol as a valid THING.
+
+The value is a cons cell (START . END) giving the start and end positions
+of the textual entity that was found."
(let ((orig (point)))
(condition-case nil
(save-excursion
+ ;; Try moving forward, then back.
(let ((end (progn
(funcall
- (or (get THING 'end-op)
- (function (lambda () (forward-thing THING 1)))))
+ (or (get thing 'end-op)
+ (function (lambda () (forward-thing thing 1)))))
(point)))
(beg (progn
(funcall
- (or (get THING 'beginning-op)
- (function (lambda () (forward-thing THING -1)))))
+ (or (get thing 'beginning-op)
+ (function (lambda () (forward-thing thing -1)))))
+ (point))))
+ (if (not (and beg (> beg orig)))
+ ;; If that brings us all the way back to ORIG,
+ ;; it worked. But END may not be the real end.
+ ;; So find the real end that corresponds to BEG.
+ (let ((real-end
+ (progn
+ (funcall
+ (or (get thing 'end-op)
+ (function (lambda () (forward-thing thing 1)))))
+ (point))))
+ (if (and beg real-end (<= beg orig) (<= orig real-end))
+ (cons beg real-end)))
+ (goto-char orig)
+ ;; Try a second time, moving backward first and then forward,
+ ;; so that we can find a thing that ends at ORIG.
+ (let ((beg (progn
+ (funcall
+ (or (get thing 'beginning-op)
+ (function (lambda () (forward-thing thing -1)))))
+ (point)))
+ (end (progn
+ (funcall
+ (or (get thing 'end-op)
+ (function (lambda () (forward-thing thing 1)))))
+ (point)))
+ (real-beg
+ (progn
+ (funcall
+ (or (get thing 'end-op)
+ (function (lambda () (forward-thing thing -1)))))
(point))))
- (if (and beg end (<= beg orig) (< orig end))
- (cons beg end))))
+ (if (and real-beg end (<= real-beg orig) (<= orig end))
+ (cons real-beg end))))))
(error nil))))
;;;###autoload
-(defun thing-at-point (THING)
- "Return the THING at point, where THING is an entity defined by
-bounds-of-thing-at-point."
- (let ((bounds (bounds-of-thing-at-point THING)))
+(defun thing-at-point (thing)
+ "Return the THING at point.
+THING is a symbol which specifies the kind of syntactic entity you want.
+Possibilities include `symbol', `list', `sexp', `defun', `filename', `url',
+`word', `sentence', `whitespace', `line', `page' and others.
+
+See the file `thingatpt.el' for documentation on how to define
+a symbol as a valid THING."
+ (let ((bounds (bounds-of-thing-at-point thing)))
(if bounds
(buffer-substring (car bounds) (cdr bounds)))))
-;;=== Go to beginning/end =================================================
+;; Go to beginning/end
-(defun beginning-of-thing (THING)
- (let ((bounds (bounds-of-thing-at-point THING)))
- (or bounds (error "No %s here" THING))
+(defun beginning-of-thing (thing)
+ (let ((bounds (bounds-of-thing-at-point thing)))
+ (or bounds (error "No %s here" thing))
(goto-char (car bounds))))
-(defun end-of-thing (THING)
- (let ((bounds (bounds-of-thing-at-point THING)))
- (or bounds (error "No %s here" THING))
+(defun end-of-thing (thing)
+ (let ((bounds (bounds-of-thing-at-point thing)))
+ (or bounds (error "No %s here" thing))
(goto-char (cdr bounds))))
-;;=== Special cases =======================================================
+;; Special cases
-;;--- Sexps ---
+;; Lines
+
+;; bolp will be false when you click on the last line in the buffer
+;; and it has no final newline.
+
+(put 'line 'beginning-op
+ (function (lambda () (if (bolp) (forward-line -1) (beginning-of-line)))))
+
+;; Sexps
(defun in-string-p ()
(let ((orig (point)))
(put 'sexp 'end-op 'end-of-sexp)
-;;--- Lists ---
+;; Lists
(put 'list 'end-op (function (lambda () (up-list 1))))
(put 'list 'beginning-op 'backward-sexp)
-;;--- Filenames ---
+;; Filenames and URLs
-(defvar file-name-chars "~/A-Za-z0-9---_.${}#%,"
+(defvar thing-at-point-file-name-chars "~/A-Za-z0-9---_.${}#%,:"
"Characters allowable in filenames.")
(put 'filename 'end-op
- (function (lambda () (skip-chars-forward file-name-chars))))
+ '(lambda () (skip-chars-forward thing-at-point-file-name-chars)))
(put 'filename 'beginning-op
- (function (lambda () (skip-chars-backward file-name-chars (point-min)))))
+ '(lambda () (skip-chars-backward thing-at-point-file-name-chars)))
+
+(defvar thing-at-point-url-chars "~/A-Za-z0-9---_@$%&=.,"
+ "Characters allowable in a URL.")
-;;--- Whitespace ---
+(put 'url 'end-op
+ '(lambda () (skip-chars-forward (concat ":" thing-at-point-url-chars))
+ (skip-chars-backward ".,:")))
+(put 'url 'beginning-op
+ '(lambda ()
+ (skip-chars-backward thing-at-point-url-chars)
+ (or (= (preceding-char) ?:)
+ (error "No URL here"))
+ (forward-char -1)
+ (skip-chars-backward "a-zA-Z")))
-(defun forward-whitespace (ARG)
+;; Whitespace
+
+(defun forward-whitespace (arg)
(interactive "p")
- (if (natnump ARG)
- (re-search-forward "[ \t]+\\|\n" nil nil ARG)
- (while (< ARG 0)
- (if (re-search-backward "[ \t]+\\|\n" nil nil)
+ (if (natnump arg)
+ (re-search-forward "[ \t]+\\|\n" nil 'move arg)
+ (while (< arg 0)
+ (if (re-search-backward "[ \t]+\\|\n" nil 'move)
(or (eq (char-after (match-beginning 0)) 10)
(skip-chars-backward " \t")))
- (setq ARG (1+ ARG)))))
+ (setq arg (1+ arg)))))
-;;--- Buffer ---
+;; Buffer
(put 'buffer 'end-op 'end-of-buffer)
(put 'buffer 'beginning-op 'beginning-of-buffer)
-;;--- Symbols ---
+;; Symbols
-(defun forward-symbol (ARG)
+(defun forward-symbol (arg)
(interactive "p")
- (if (natnump ARG)
- (re-search-forward "\\(\\sw\\|\\s_\\)+" nil nil ARG)
- (while (< ARG 0)
- (if (re-search-backward "\\(\\sw\\|\\s_\\)+" nil nil)
+ (if (natnump arg)
+ (re-search-forward "\\(\\sw\\|\\s_\\)+" nil 'move arg)
+ (while (< arg 0)
+ (if (re-search-backward "\\(\\sw\\|\\s_\\)+" nil 'move)
(skip-syntax-backward "w_"))
- (setq ARG (1+ ARG)))))
+ (setq arg (1+ arg)))))
+
+;; Syntax blocks
+
+(defun forward-same-syntax (&optional arg)
+ (interactive "p")
+ (while (< arg 0)
+ (skip-syntax-backward
+ (char-to-string (char-syntax (char-after (1- (point))))))
+ (setq arg (1+ arg)))
+ (while (> arg 0)
+ (skip-syntax-forward (char-to-string (char-syntax (char-after (point)))))
+ (setq arg (1- arg))))
-;;=== Aliases =============================================================
+;; Aliases
(defun word-at-point () (thing-at-point 'word))
(defun sentence-at-point () (thing-at-point 'sentence))
-(defun read-from-whole-string (STR)
- "Read a lisp expression from STR, signalling an error if the entire string
-was not used."
- (let* ((read-data (read-from-string STR))
+(defun read-from-whole-string (str)
+ "Read a lisp expression from STR.
+Signal an error if the entire string was not used."
+ (let* ((read-data (read-from-string str))
(more-left
(condition-case nil
- (progn (read-from-string (substring STR (cdr read-data)))
+ (progn (read-from-string (substring str (cdr read-data)))
t)
(end-of-file nil))))
(if more-left
(error "Can't read whole string")
(car read-data))))
-(defun form-at-point (&optional THING PRED)
+(defun form-at-point (&optional thing pred)
(let ((sexp (condition-case nil
- (read-from-whole-string (thing-at-point (or THING 'sexp)))
+ (read-from-whole-string (thing-at-point (or thing 'sexp)))
(error nil))))
- (if (or (not PRED) (funcall PRED sexp)) sexp)))
+ (if (or (not pred) (funcall pred sexp)) sexp)))
(defun sexp-at-point () (form-at-point 'sexp))
(defun symbol-at-point () (form-at-point 'sexp 'symbolp))
HCoop / bpt / emacs.git / blobdiff