[CMake] How to test for the usability of a target

[Johannes Zarl]

On Wednesday, 16. October 2013, 19:45:32, Alexander Neundorf wrote:
> On Tuesday 15 October 2013, Johannes Zarl wrote:
> > I'd like to make some code in my build system dependent on the existance
> > of a target. Basically I'd like to write something like this:
> > 
> > if(TARGET optional_lib)
> > 
> >   add_library(bar ${bar_srcs})
> >   target_link_library(bar optional_lib)
> > 
> > endif()
> > 
> Can generator expressions maybe be used for that ?
> They are evaluated at generate time, so at a time when the target is know
> to exist or not.

Yes, that should probably work for my use case. I hadn't thought of that.

Thanks!
  Johannes