Re: Little improvements on pulse.el

[Eli Zaretskii <eliz@gnu.org>]

> From: Gabriel <gabriel376@hotmail.com>
> Date: Wed, 10 Mar 2021 02:39:56 -0300
> 
> I have been playing with pulse.el in the last few days and some
> ideas/questions come to my mind.

Thanks.

> 1. It can be useful in some cases to pulse the current line by using an
> interactive command, for example, when doing a presentation, a pairing
> with other developer, or to easily find the cursor position. Since
> 'pulse-line-hook-function' is not a good name for an interactive
> function, we can create a new command for that.

How about pulse-line-command?  Or even just pulse-line?

> 2. The name and the docstring mention the use with hooks, but would be
> nice to use with advices as well. For example, to highlight the current
> line when the cursor, buffer or window changes:
> 
> (dolist (symbol '(scroll-up-command
>                   scroll-down-command
>                   recenter-top-bottom
>                   other-window
>                   windmove-do-window-select
>                   kill-current-buffer
>                   delete-window))
>   (advice-add symbol :after #'pulse-line-hook-function))
> 
> The code above does not work, since 'pulse-line-hook-function' does not
> accept any argument (sent by the advice function). We can make it accept
> optional arguments, but again the name will not be the best one.

I'd prefer not to use advices for such a simple job.  For example, how
about defining a new hook, which will receive the argument(s) you want
to pass it?

> 3. I could not find any documentation or usage in emacs source code for
> 'pulse-line-hook-function' and 'pulse-command-advice-flag'. Is the flag
> 'pulse-command-advice-flag' really needed ? The git history says the
> last modification of this code was 12+ years ago.

You will find one usage of the hook in CEDET.  In any case, after so
many years I don't think we should consider removing these without a
good reason.  Is there such a reason?

> 4. Would be nice to have support for 'pulse-highlight-start-face' in the
> themes provided by Emacs, especially on modus-themes.

That's up to the themes, no?  They don't necessarily modify all the
faces.

> 5. The code on 'pulse-lighten-highlight' can be significantly improved
> by replacing 'pulse-int-to-hex' and 'pulse-color-values-to-hex' with
> 'color-gradient' from color.el. The idea is to build the list of color
> gradients beforehand and use a timer to set each color according to
> 'pulse-iterations' and 'pulse-delay'. A very basic example:

I'm not sure I understand the improvement, can you elaborate?