Re: Select completions from the minibuffer

[Juri Linkov]

>>> >Isn't it very similar to the region?
>>>
>>> I don't think so... I think it is more similar to the mouse-face
>>> feature / text property.
>>
>>Why do you think so?  The region is redrawn when the cursor moves, and
>>the cursor moves as result of Emacs commands, so how is this very
>>different from what you want?  By contrast, the mouse highlight is
>>triggered by mouse movements that are completely independent of Emacs
>>commands, and the implementation, as part of the display engine, is
>>therefore quite complicated.  Whereas the region display is nowadays
>>implemented completely in Lisp.
>
> Ok, then it will be similar to the code I already have in
> completions-highlight-mode.  Essentially add/move an overlay on post
> command hook based on some conditions.

You could just add your function to the default value of
pre-redisplay-functions, e.g.

  (defvar pre-redisplay-functions (list #'redisplay--update-region-highlight
                                        #'redisplay--update-mouse-face)

where the new function 'redisplay--update-mouse-face'
will activate the mouse-face when the cursor moves
over the mouse-face property (only when an additional user option
will be enabled).