[Haskell-cafe] Building examples with Cabal

[Sven Panne]

2013/10/16 Heinrich Apfelmus <apfelmus at quantentunnel.de>:
> I usually declare an "Executable" for each example and add a flag
> "buildExamples" that controls whether the examples are built or not. Here an
> example .cabal file.
>
> http://hackage.haskell.org/package/threepenny-gui-0.3.0.0/threepenny-gui.cabal

I tried something similar in the past, but that didn't really work out:

  * Things get *extremely* verbose and repetitive in the .cabal file.
Currently there are roughly 90 GLUT examples, and I expect to have
much more in the future. This would lead to more than 1000 lines of
boilerplate .cabal stuff. OK, Emacs macros and copy-n-paste are your
friends, but... :-P

  * Can Cabal build the executables in parallel? Doing a parallel
build of all examples via my make hack takes about 5 seconds, a
non-parallel build takes 75 seconds, and I expect that gap to widen
even more when I add more examples.

  * How does one handle common parts in the examples? (e.g.
https://github.com/haskell-opengl/GLUT/tree/master/examples/RedBook8/common,
more to come there) Conditionally build helper libraries just for the
examples?

I can't believe that I'm the only package maintainer who has such a
problem, so I really hope that there is some hidden solution out there
I simply can't see...