On Nov 15, 2006, at 4:48 PM, David Abrahams wrote:

> Perry Smith <pedz@easesoftware.com> writes:
>
>> On Nov 15, 2006, at 2:10 PM, David Abrahams wrote:
>>
>>     Hi,
>>
>>     Could someone tell me how to get the effect of an "activated  
>> mark" in
>>     transient mark mode from within elisp?  In other words, I'd  
>> like to be
>>     able to set up the point and mark, and when my elisp  
>> completes, see
>>     the region highlighted.  Seems like it should be simple, but  
>> nothing I
>>     do seems to work.
>>
>> You might be asking how transient mark mode works.
>
> I don't think that's what I'm asking.
>
>> It seems to be just a variable that commands look at.  But this
>> works for me:
>>
>> (defun dog-test ()
>>  (interactive)
>>  (transient-mark-mode 1)
>>  (set-mark (point))
>>  (forward-char 20))
>>
>> execute dog-test from the minibuffer and the current point plus 20
>> characters are highlighted
>
> Not for me. :(
>
> Thanks for responding.

I felt challenged :-)

You make a face.  Put the attributes that you want in it.  Then use  
put-text-property to apply that face to the region.

(make-face 'my-blue-face)

(set-face-attribute 'my-blue-face nil :background "blue")

(defun dog-test3 ()
   (interactive)
   (put-text-property (point) (mark) 'face 'my-blue-face))

Set your mark and point, then do M-x dog-test3

There is something I don't understand though.  If you have font-lock- 
mode set, then it does not work.  I'm not sure what is happening in  
that case.  I'm curious to see if others reply.

Hope this help...
Perry Smith
Ease Software, Inc.
pedz@easesoftware.com
http://www.easesoftware.com

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