mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-14 09:39:42 +00:00
399 lines
13 KiB
EmacsLisp
399 lines
13 KiB
EmacsLisp
;;; thingatpt.el --- get the `thing' at point
|
|
|
|
;; Copyright (C) 1991,92,93,94,95,96,97,1998,2000
|
|
;; Free Software Foundation, Inc.
|
|
|
|
;; Author: Mike Williams <mikew@gopher.dosli.govt.nz>
|
|
;; Maintainer: FSF
|
|
;; Keywords: extensions, matching, mouse
|
|
;; Created: Thu Mar 28 13:48:23 1991
|
|
|
|
;; 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 2, 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.
|
|
|
|
;;; 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
|
|
;; 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
|
|
;; backwards to the beginning. By default, it uses the corresponding
|
|
;; forward-"thing" operator (eg. forward-word, forward-line).
|
|
;;
|
|
;; Special cases are allowed for using properties associated with the named
|
|
;; "thing":
|
|
;;
|
|
;; 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".
|
|
;;
|
|
;; Reliance on existing operators means that many `things' can be accessed
|
|
;; without further code: eg.
|
|
;; (thing-at-point 'line)
|
|
;; (thing-at-point 'page)
|
|
|
|
;;; Code:
|
|
|
|
(provide 'thingatpt)
|
|
|
|
;; Basic movement
|
|
|
|
;;;###autoload
|
|
(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)))))
|
|
(if (functionp forward-op)
|
|
(funcall forward-op (or n 1))
|
|
(error "Can't determine how to move over a %s" thing))))
|
|
|
|
;; General routines
|
|
|
|
;;;###autoload
|
|
(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."
|
|
(if (get thing 'bounds-of-thing-at-point)
|
|
(funcall (get thing 'bounds-of-thing-at-point))
|
|
(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)))))
|
|
(point)))
|
|
(beg (progn
|
|
(funcall
|
|
(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 'beginning-op)
|
|
(function (lambda () (forward-thing thing -1)))))
|
|
(point))))
|
|
(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.
|
|
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."
|
|
(if (get thing 'thing-at-point)
|
|
(funcall (get thing 'thing-at-point))
|
|
(let ((bounds (bounds-of-thing-at-point thing)))
|
|
(if bounds
|
|
(buffer-substring (car bounds) (cdr bounds))))))
|
|
|
|
;; Go to beginning/end
|
|
|
|
(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))
|
|
(goto-char (cdr bounds))))
|
|
|
|
;; Special cases
|
|
|
|
;; 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)))
|
|
(save-excursion
|
|
(beginning-of-defun)
|
|
(nth 3 (parse-partial-sexp (point) orig)))))
|
|
|
|
(defun end-of-sexp ()
|
|
(let ((char-syntax (char-syntax (char-after (point)))))
|
|
(if (or (eq char-syntax ?\))
|
|
(and (eq char-syntax ?\") (in-string-p)))
|
|
(forward-char 1)
|
|
(forward-sexp 1))))
|
|
|
|
(put 'sexp 'end-op 'end-of-sexp)
|
|
|
|
(defun beginning-of-sexp ()
|
|
(let ((char-syntax (char-syntax (char-before (point)))))
|
|
(if (or (eq char-syntax ?\()
|
|
(and (eq char-syntax ?\") (in-string-p)))
|
|
(forward-char -1)
|
|
(forward-sexp -1))))
|
|
|
|
(put 'sexp 'beginning-op 'beginning-of-sexp)
|
|
|
|
;; Lists
|
|
|
|
(put 'list 'end-op (function (lambda () (up-list 1))))
|
|
(put 'list 'beginning-op 'backward-sexp)
|
|
|
|
;; Filenames and URLs
|
|
|
|
(defvar thing-at-point-file-name-chars "~/A-Za-z0-9---_.${}#%,:"
|
|
"Characters allowable in filenames.")
|
|
|
|
(put 'filename 'end-op
|
|
(lambda () (skip-chars-forward thing-at-point-file-name-chars)))
|
|
(put 'filename 'beginning-op
|
|
(lambda () (skip-chars-backward thing-at-point-file-name-chars)))
|
|
|
|
(defvar thing-at-point-url-path-regexp
|
|
"[^]\t\n \"'()<>[^`{}]*[^]\t\n \"'()<>[^`{}.,;]+"
|
|
"A regular expression probably matching the host, path or e-mail part of a URL.")
|
|
|
|
(defvar thing-at-point-short-url-regexp
|
|
(concat "[-A-Za-z0-9.]+" thing-at-point-url-path-regexp)
|
|
"A regular expression probably matching a URL without an access scheme.
|
|
Hostname matching is stricter in this case than for
|
|
``thing-at-point-url-regexp''.")
|
|
|
|
(defvar thing-at-point-url-regexp
|
|
(concat
|
|
"\\<\\(https?://\\|ftp://\\|gopher://\\|telnet://\\|wais://\\|file:/\\|s?news:\\|mailto:\\)"
|
|
thing-at-point-url-path-regexp)
|
|
"A regular expression probably matching a complete URL.")
|
|
|
|
(defvar thing-at-point-markedup-url-regexp
|
|
"<URL:[^>]+>"
|
|
"A regular expression matching a URL marked up per RFC1738.
|
|
This may contain whitespace (including newlines) .")
|
|
|
|
(put 'url 'bounds-of-thing-at-point 'thing-at-point-bounds-of-url-at-point)
|
|
(defun thing-at-point-bounds-of-url-at-point ()
|
|
(let ((url "") short strip)
|
|
(if (or (setq strip (thing-at-point-looking-at
|
|
thing-at-point-markedup-url-regexp))
|
|
(thing-at-point-looking-at thing-at-point-url-regexp)
|
|
;; Access scheme omitted?
|
|
(setq short (thing-at-point-looking-at
|
|
thing-at-point-short-url-regexp)))
|
|
(let ((beginning (match-beginning 0))
|
|
(end (match-end 0)))
|
|
(cond (strip
|
|
(setq beginning (+ beginning 5))
|
|
(setq end (- end 1))))
|
|
(cons beginning end)))))
|
|
|
|
(put 'url 'thing-at-point 'thing-at-point-url-at-point)
|
|
(defun thing-at-point-url-at-point ()
|
|
"Return the URL around or before point.
|
|
|
|
Search backwards for the start of a URL ending at or after point. If
|
|
no URL found, return nil. The access scheme will be prepended if
|
|
absent: \"mailto:\" if the string contains \"@\", \"ftp://\" if it
|
|
starts with \"ftp\" and not \"ftp:/\", or \"http://\" by default."
|
|
|
|
(let ((url "") short strip)
|
|
(if (or (setq strip (thing-at-point-looking-at
|
|
thing-at-point-markedup-url-regexp))
|
|
(thing-at-point-looking-at thing-at-point-url-regexp)
|
|
;; Access scheme omitted?
|
|
(setq short (thing-at-point-looking-at
|
|
thing-at-point-short-url-regexp)))
|
|
(progn
|
|
(setq url (buffer-substring-no-properties (match-beginning 0)
|
|
(match-end 0)))
|
|
(and strip (setq url (substring url 5 -1))) ; Drop "<URL:" & ">"
|
|
;; strip whitespace
|
|
(while (string-match "[ \t\n\r]+" url)
|
|
(setq url (replace-match "" t t url)))
|
|
(and short (setq url (concat (cond ((string-match "@" url)
|
|
"mailto:")
|
|
;; e.g. ftp.swiss... or ftp-swiss...
|
|
((string-match "^ftp" url)
|
|
"ftp://")
|
|
(t "http://"))
|
|
url)))
|
|
(if (string-equal "" url)
|
|
nil
|
|
url)))))
|
|
|
|
;; The normal thingatpt mechanism doesn't work for complex regexps.
|
|
;; This should work for almost any regexp wherever we are in the
|
|
;; match. To do a perfect job for any arbitrary regexp would mean
|
|
;; testing every position before point. Regexp searches won't find
|
|
;; matches that straddle the start position so we search forwards once
|
|
;; and then back repeatedly and then back up a char at a time.
|
|
|
|
(defun thing-at-point-looking-at (regexp)
|
|
"Return non-nil if point is in or just after a match for REGEXP.
|
|
Set the match data from the earliest such match ending at or after
|
|
point."
|
|
(save-excursion
|
|
(let ((old-point (point)) match)
|
|
(and (looking-at regexp)
|
|
(>= (match-end 0) old-point)
|
|
(setq match (point)))
|
|
;; Search back repeatedly from end of next match.
|
|
;; This may fail if next match ends before this match does.
|
|
(re-search-forward regexp nil 'limit)
|
|
(while (and (re-search-backward regexp nil t)
|
|
(or (> (match-beginning 0) old-point)
|
|
(and (looking-at regexp) ; Extend match-end past search start
|
|
(>= (match-end 0) old-point)
|
|
(setq match (point))))))
|
|
(if (not match) nil
|
|
(goto-char match)
|
|
;; Back up a char at a time in case search skipped
|
|
;; intermediate match straddling search start pos.
|
|
(while (and (not (bobp))
|
|
(progn (backward-char 1) (looking-at regexp))
|
|
(>= (match-end 0) old-point)
|
|
(setq match (point))))
|
|
(goto-char match)
|
|
(looking-at regexp)))))
|
|
|
|
(put 'url 'end-op
|
|
(function (lambda ()
|
|
(let ((bounds (thing-at-point-bounds-of-url-at-point)))
|
|
(if bounds
|
|
(goto-char (cdr bounds))
|
|
(error "No URL here"))))))
|
|
(put 'url 'beginning-op
|
|
(function (lambda ()
|
|
(let ((bounds (thing-at-point-bounds-of-url-at-point)))
|
|
(if bounds
|
|
(goto-char (car bounds))
|
|
(error "No URL here"))))))
|
|
|
|
;; Whitespace
|
|
|
|
(defun forward-whitespace (arg)
|
|
(interactive "p")
|
|
(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)))))
|
|
|
|
;; Buffer
|
|
|
|
(put 'buffer 'end-op (lambda () (goto-char (point-max))))
|
|
(put 'buffer 'beginning-op (lambda () (goto-char (point-min))))
|
|
|
|
;; Symbols
|
|
|
|
(defun forward-symbol (arg)
|
|
(interactive "p")
|
|
(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)))))
|
|
|
|
;; 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
|
|
|
|
(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.
|
|
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)))
|
|
t)
|
|
(end-of-file nil))))
|
|
(if more-left
|
|
(error "Can't read whole string")
|
|
(car read-data))))
|
|
|
|
(defun form-at-point (&optional thing pred)
|
|
(let ((sexp (condition-case nil
|
|
(read-from-whole-string (thing-at-point (or thing 'sexp)))
|
|
(error nil))))
|
|
(if (or (not pred) (funcall pred sexp)) sexp)))
|
|
|
|
;;;###autoload
|
|
(defun sexp-at-point () (form-at-point 'sexp))
|
|
;;;###autoload
|
|
(defun symbol-at-point () (form-at-point 'sexp 'symbolp))
|
|
;;;###autoload
|
|
(defun number-at-point () (form-at-point 'sexp 'numberp))
|
|
;;;###autoload
|
|
(defun list-at-point () (form-at-point 'list 'listp))
|
|
|
|
;;; thingatpt.el ends here
|