Re: Question about 'provides' and emacs packaging

[Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>]

On 2021-10-05 09:51, Ken Brown via Cygwin-apps wrote:
> 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?

Hi Ken,

Achim recently restructured gnuplot; I used to install gnuplot, 
gnuplot-base now obsoletes that, and that is all I have installed; 
alternatives handles the priorities if different packages provide gnuplot:

https://cygwin.com/git-cygwin-packages/?p=git/cygwin-packages/gnuplot.git

gnuplot-base
depends2: cygwin, libcairo2, libcerf1, libgd3, libglib2.0_0, liblua5.3, 
libpango1.0_0, libreadline7

gnuplot-X11
depends2: cygwin, gnuplot-base, libX11_6, <BASE-DEPENDS2>...

gnuplot-qt5
depends2: cygwin, gnuplot-X11, libQt5Core5, libQt5Gui5, libQt5Svg5, 
libgcc1, <BASE-DEPENDS2>... libstdc++6

gnuplot-wx
depends2: cygwin, gnuplot-X11, libgcc1, <BASE-DEPENDS2>... libgtk3_0, 
libstdc++6, libwx_baseu3.0_0, libwx_gtk3u3.0_0

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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