Standard for placing any template Find-modules with the original lib? (was: Re: Strange commit to FindKDE4Internal.cmake)

[Alexander Neundorf]

On Friday 17 February 2012, Friedrich W. H. Kossebau wrote:
> Am Freitag, 17. Februar 2012, 17:33:34 schrieb Alexander Neundorf:
> > A library must never install the Find-module for itself.
> > 
> > This defeats the purpose. This is like putting the remote control right
> > next to the TV, or the treasure map right into the treasure chest. You
> > don't know where the plan is, but once you found the plan, you already
> > found what you are interested in and don't need the plan anymore.
> 
> That reminds me of something I wanted to ask for a while:
> 
> A few libraries provide in their sources a template for the Find-module for
> itselves, as a nice starting point for devs using the lib and needing that
> Find-module.
> 
> But IIRC those libs had the template file in the same "cmake/modules"
> subdir where also the normal Find-modules which are actually used by the
> lib's buildsystem are located. A little bit confusing, at least for me the
> template file would be ideally in a separate file and even have a special
> name, like "Find*.cmake.template" or similar, to help discoverability.
> 
> Do you have a proposal or know a pattern-to-follow how to name and where to
> place such Find-module templates? Would be nice if there could be some
> standard.
> 
> E.g. for my RIFF-parser lib libkoralle I would like to ship a template
> Find- module, but also want any user of the lib discover what I provided
> for them, so my work is not uselessly duplicated. Placing that in
> extra-cmake-modules would help only KDE-centric devs, no?

No, extra-cmake-modules will have no KDE dependencies at all, it is 
explicitely meant for everybody (which also includes KDE).

There will be the first release this spring or early summer, at the latest at 
the same time of the first KDE frameworks alpha/beta/preview/whatever release.

So, if you want to distribute a Find-module, without getting it into cmake, 
but also without any additional dependencies, extra-cmake-modules will be the 
place to put it.

Beside that, a library built with cmake should install a FooConfig.cmake file 
for itself. This is in principle similar to the concept from pkg_config, but 
more powerful. It is described here: 
http://www.cmake.org/Wiki/CMake/Tutorials#CMake_Packages
http://www.cmake.org/Wiki/CMake/Tutorials/How_to_create_a_ProjectConfig.cmake_file

Getting it completely right is currently a bit complicated, and I am right now 
working on making it easier. This will be in cmake 2.8.8.


Alex