[QBS] Properties and base.concat

[Joerg Bornemann]

On 05/03/2012 14:43, ext Tom Sutcliffe wrote:

> * Specifying cpp.defines as a raw list is almost always the wrong thing
> to do - ie this is bad: cpp.defines: ["MY_DEFINE"]
> * Almost always you should be using base.concat - ie: cpp.defines:
> base.concat(["MY_DEFINE"])
> * Inside a group, you should probably use
> outer.concat(["GROUP_SPECIFIC_DEFINE"])

This is correct for the current situation and I do not like it very 
much. It should be ok to just use
       cpp.defines: ["MY_DEFINE"]
in a project but ATM this will override the value of cpp.defines the cpp 
module initially sets.

I propose to have cpp.defines initially empty and have another property 
for initial defines.

---CppModule.qbs---
property var defines: []

---windows-mingw.qbs---
property var platformDefines: ['UNICODE']

---myproject.qbp---
Application {
     Depends { name: "cpp" }
     cpp.defines: ['MY_DEFINE']
     //override cpp.platformDefines if needed
}

> Are there any other properties that we need to be wary of assigning
> directly to because of stuff done behind the scenes? Eg cpp.includePath?
> Is cpp.defines going to become enough of a gotcha that it'd be better to
> define UNICODE etc some other way (similar to what you said in your
> other mail I guess?). Is there any legitimate situation where you might
> want to exploit this behaviour to undefine a platform-defined macro?

For now its only the defines. Initial values for defines, includes and 
libs etc. in other modules than cpp are ok (like in qtcore or so).


Jörg