Brad King wrote: > On 06/05/2012 04:59 PM, Stephen Kelly wrote: >> So far we don't have agreement about how this should look language-wise >> as far as I can tell. I agree with David that stuffing it into the >> strings harms readability. > [snip] >> generator_expression(myGenExpr) > [snip] >> The $<GENERATOR:someName> could similarly be used for defines and other >> places where we are discussing adding this feature. > > That is an interesting idea to keep in mind for the future but I think > the implementation of it is too tricky to be in scope now.
That's a little unfortunate. I'm not familiar enough with the existing implementation to understand why yet that is so. I do see some benefits implementation-wise of your idea below though. <snip> > $<CONFIG:...> evaluates to 0 or 1 if config matches ... > $<LANGUAGE:...> evaluates to 0 or 1 if language matches ... > $<TARGET_PROPERTY_BOOL:WIN32_EXECUTABLE,tgt> = 0 or 1 Are you sure about this one? Given your further explanation below, and assuming the intention is 'link to tgt if *this has a WIN32_EXECUTABLE property which is True', it should rather be: $<$<TARGET_PROPERTY_BOOL:WIN32_EXECUTABLE>:tgt> ? Otherwise I have failed to parse it. <snip> > $<$<CONFIG:Debug>:/path/for/Debug> > $<$<NOT:$<CONFIG:Debug>>:/path/for/non-Debug> > $<$<AND:$<CONFIG:Debug>,$<LANGUAGE:CXX>>:/path/for/Debug/Cxx> There's a lot of repetition, at least in these examples. If there's a lot also in the real world, it might be more maintenance burden than convenience. The fact that it is also a new language syntax that needs to be learned and spread might also make it not-great for adoption/uptake. > Each individual expression is easy to define, document, and > implement. Each has a very strict syntax we can validate as > part of the implementation and parsing, thus allowing future > extensions. They look like existing generator expressions and > follow a functional style. And at least if it makes sense in the future (and the parser is strict enough) we can implement my idea too. Thanks, Steve. -- Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ Follow this link to subscribe/unsubscribe: http://public.kitware.com/cgi-bin/mailman/listinfo/cmake-developers
