Re: Adding Emms to ELPA (take 2), and a technical question

[Stefan Monnier <monnier@iro.umontreal.ca>]

> The main issue back then was that Emms was a copyright mess. Stefan
> Monnier helped me figuring out who to contact and I've fixed that since
> (took a while). To the best of my knowledge, everyone who has code in
> Emms has an assignment on file. Emms has an AUTHORS file which is kept
> up-to-date. Everyone there should also appear in the FSF records.

Great news, thank you!

> Stefan also said that ELPA packages need to have their .el files at the
> top-level.  However, Emms has its files in a lisp/ directory. This is
> still the case, and I would like to keep it that way because Emms has a
> lot of files and a lisp/ directory keeps things tidy. Is this still a
> requirement for ELPA?

Yes, and you even wrote it right: it's a property of ELPA (and not
specific to GNU ELPA), so it affects MELPA just as well.  This comes
from the fact that only top-level files are scanned for `;;;###autoload`
cookies when the package is installed.

You can work around this problem with extra work, tho: build your own
autoloads file for the files in `lisp/*.el` and distribute it as if it
were a "source" file.

The Hyperbole package does that for its `kotl` subdirectory:
they "manually" builds&updates a `kotl/kotl-autoloads.el` file (the rule
to update it is in a Makefile), and then in `hyperbole.el` they have:

    ;;;###autoload (load "kotl/kotl-autoloads" nil 'nowarn)

> Emms also comes with a small piece of code that needs to be compiled in
> order to use taglib (https://taglib.org/). The code is in a src/
> directory in the Emms distribution. I understand that there is no way to
> get ELPA to compile something as a part of the installation.

Yes, there is.  You can put something like:

    (eval-when-compile (call-process "make"))

in your main file, for example.

> We can forgo any compilation at the ELPA installation stage as long as
> people get to read the excellent Emms manual which explains how (and
> why) to compile that bit of code.  Would any of this be a problem for
> adding Emms to ELPA?

These will require extra work on your part, but other than that, no,
they don't impact your ability to add the package to GNU ELPA.

> We (the Emms developers) are desperately looking for a better way to
> give Emms access to taglib other than compiling glue code like we do
> now. We really don't want to ship C, or C++, or Perl, or anything except
> elisp with Emms. One option we are currently exploring is to ask the
> user to install an existing package such as pytaglib (a GPLv3 python
> wrapper around taglib). Is there any more elegant way to get access to
> taglib through Emacs that anyone can suggest?

I'm afraid I don't have a better solution to offer.


        Stefan