Re: [ELPA] New package: progress-bar

[Stefan Kangas <stefankangas@gmail.com>]

Mariano Montone <marianomontone@gmail.com> writes:

> I'd be glad if someone can have a look and give me an opinion, and if
> there's potential to integrate to Emacs after I improve it, make it
> solid, and provide a backwards compatible interface for current Emacs'
> progress-report.

I think that we would be interested in adding such functionality to
Emacs, yes.

What I would find useful is a new user option to choose between
different styles of display for the built-in progress reporters.  Some
of them could take full advantage of the capabilities on graphical
displays, for example (i.e. SVG or somesuch), and others would be more
basic (i.e. what we have now, or some ASCII/Unicode art).

Here's where I would start: make it possible to plug in various
implementations, and then make `progress-reporter-do-update' choose
between them.  The way I imagine this is that you have several
predefined "displayer" (or simply "display"?) functions that are all
called in the same way.  Then `progress-reporter-do-update' would simply
make any necessary calculations, and then call a display function.

To customize this, the user could set some new user option (i.e. a
`defcustom') to a symbol like `default', `bar', `ignore', etc., and then
that would make `progress-reporter-do-update' call the correct function.
We could also allow setting the option to some function that has the
same call signature as the predefined ones.

The first displayer to implement, of course, is `default', which is just
simply what we have now.  Once you have that working, it should be
easier to add more.  And indeed, adding more is probably the best way to
figure out what is a reasonable call signature that all displayer
functions should have.

If you are interested in working on this, I suggest that you write up a
patch for emacs.git and send it to the bug-gnu-emacs list.  Thanks!