[cmake-developers] [Discussion] Add python support for CMakeLists

[Stephen Kelly]

Florent Castelli wrote:

> Well, CMake scripts can be written in a somewhat declarative form now.
> What prevents this now is that a lot of people use indirections
> everywhere. For example: add_library(foo STATIC ${SRCS}) If it was a plain
> list, any decent IDE would be able to parse this and add another file to
> the list easily. If some commands allowed more expressive alternative
> forms, it would definitely improve the situation:
> 
> add_library(foo STATIC
>   bar1.c
>   bar2.c
>   WINDOWS
>   windows-specific.c
>   APPLE
>   apple-specific.m
> )

It's up to users to use generator expressions instead of if(WIN32) or 
whatever:

 add_library(foo
   foo.cpp
   $<$<PLATFORM_ID:Windows>:foo_win.cpp>
 )

This has been possible for years and was designed with IDEs in mind:

 http://public.kitware.com/pipermail/cmake-developers/2014-September/023042.html

> I find that most of the conditionals are just to create the list of
> sources per platform and then the list of dependencies. It’s certainly
> possible to use generator expressions for some cases, but they don’t have
> the prettiest syntax around, and maybe also not access to all the local
> variables that you need to pick the right files.

You should be able to put any configure-time variable through the generator 
expressions $<BOOL> or $<STREQUAL> to make them genex-compatible.

Thanks,

Steve.