[CMake] Setting properties from within a function

[Michael Surette]

On 2016-04-12 06:57 PM, Tamás Kenéz wrote:
> I don't get how come the macro works because
> `target_compile_definitions` needs at least 3 parameters. The second one
> must be PRIVATE|PUBLIC|INTERFACE.
> Tamas
>
> On Tue, Apr 12, 2016 at 7:43 AM, Michael Surette
> <mjsurette at gmail.com
> <mailto:mjsurette at gmail.com>> wrote:
>
>     I would like to use set target properties from within a function.  ie
>
>     function(MINE TGT DEF)
>        target_compile_definitions("${TGT}" "${DEF}")
>     endfunction(MINE TGT DEF)
>
>     This doesn't work.  If I change it to a macro, it does.
>
>     macro(MINE TGT DEF)
>        target_compile_definitions("${TGT}" "${DEF}")
>     endmacro(MINE TGT DEF)
>
>     Is there a way to extend the scope of TGT in the function so that
>     the function variant works?

Good catch.

Actually, I have the (usually PRIVATE) part as the beginning of ${DEF}.

To clarify, this is a question about scoping.  If the command in the 
function was a "set" I could do

set("${TGT}" "${DEF}" PARENT_SCOPE)

In my example, what I want to do is set the target_compile_definitions 
of the name "${TGT}".  A function is preferable to a macro so I can 
avoid namespace collisions.

This is not all that this function does of course, or I would just call 
target_compile_definitions directly, but I cut out the other stuff to 
simplify the example.

Upon further thought, perhaps you are on to something, let me do some 
testing.

In the meantime, any more thoughts would be appreciated.

Mike