Adding email address support to thingatpt.el.

[Karl Fogel]

I was surprised to find that thingatpt.el doesn't support email
addresses, so made the patch below.  I'd like comments before
committing, though, as I've never modified thingatpt.el before.

If we're in a freeze, this can wait.  (I can't tell if we're in a
freeze or not, from looking at the Savannah pages for Emacs.)

-Karl

2007-02-25  Karl Fogel  <address@hidden>

   * thingatpt.el: Add support for email addresses (`email').
   (thing-at-point, bounds-of-thing-at-point): Document `email' support.
   (thing-at-point-email-regexp): New variable.
   (`email'): Put `bounds-of-thing-at-point' and `thing-at-point'
   properties on this symbol, with lambda forms for values.

Index: lisp/thingatpt.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/thingatpt.el,v
retrieving revision 1.40
diff -u -r1.40 thingatpt.el
--- lisp/thingatpt.el   21 Jan 2007 03:53:10 -0000      1.40
+++ lisp/thingatpt.el   25 Feb 2007 10:13:49 -0000
@@ -67,7 +67,7 @@
   "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.
+`email', `word', `sentence', `whitespace', `line', `page' and others.
 
 See the file `thingatpt.el' for documentation on how to define
 a symbol as a valid THING.
@@ -124,7 +124,7 @@
   "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.
+`email', `word', `sentence', `whitespace', `line', `page' and others.
 
 See the file `thingatpt.el' for documentation on how to define
 a symbol as a valid THING."
@@ -340,6 +340,33 @@
              (goto-char (car bounds))
            (error "No URL here")))))
 
+;;   Email addresses
+(defvar thing-at-point-email-regexp
+  "<\\{0,1\\}[-+_.~a-zA-Z][-+_.~:address@hidden>\\{0,1\\}"  
+  "A regular expression probably matching an email address.
+This does not match the real name portion, only the address, optionally
+with angle brackets.")
+
+;; Haven't set 'forward-op on 'email nor defined 'forward-email' because
+;; not sure they're actually needed, and URL seems to skip them too.
+;; Note that (end-of-thing 'email) and (beginning-of-thing 'email)
+;; work automagically, though.
+
+(put 'email 'bounds-of-thing-at-point
+     (lambda ()
+       (let ((thing (thing-at-point-looking-at thing-at-point-email-regexp)))
+         (if thing
+             (let ((beginning (match-beginning 0))
+                   (end (match-end 0)))
+               (cons beginning end)))))
+
+(put 'email 'thing-at-point
+     (lambda ()
+       (let ((boundary-pair (thing-at-point-bounds-of-email-at-point)))
+         (if boundary-pair
+             (buffer-substring-no-properties
+              (car boundary-pair) (cdr boundary-pair))))))
+
 ;;  Whitespace
 
 (defun forward-whitespace (arg)