Question about 'provides' and emacs packaging

[Ken Brown <kbrown@cornell.edu>]

I asked this question several years ago 
(https://cygwin.com/pipermail/cygwin-apps/2018-October/039451.html), but I'm 
repeating it, in a more specific form, in the hope that setup has progressed to 
the point where I get a different answer.

There are currently five emacs packages: emacs-common, emacs, emacs-X11, 
emacs-w32, and emacs-lucid.  The first includes things that are needed by each 
of the other four, and those four each include an emacs binary.  The binary in 
the emacs package is /usr/bin/emacs-nox.exe.  The other packages contain 
/usr/bin/emacs-X11.exe, and so on.

This way of naming the packages doesn't really reflect the contents of the emacs 
package.  It also means that anyone who installs emacs gets emacs-nox.exe, even 
if they plan to use one of the other three binaries.

I would rather rename the current emacs-common package to emacs and the current 
emacs package to emacs-nox.  But then the new emacs would have to have a way of 
requiring the installation of at least one of emacs-nox, emacs-X11, emacs-w32, 
or emacs-lucid.  Is there any way to do this with our current setup machinery?

My idea three years ago was to have the new emacs package require a "feature" 
called, for instance, emacs-bin, and then have each of emacs-nox, emacs-X11, 
emacs-w32, emacs-lucid "provide" that feature.  This is what Fedora does.  Achim 
didn't think this was feasible without major changes in setup.  Is that still 
the case?  If so, can anyone think of another way to accomplish what I want?

Thanks.

Ken