[CMake] Re: function and raise_scope commands

[Alexander Neundorf]

On Saturday 16 February 2008, Bill Hoffman wrote:
> Alexander Neundorf wrote:
> > On Friday 18 January 2008, Alexander Neundorf wrote:
...
> >> set(foo a b c PARENT_SCOPE)
> >>
> >> I'm not sure it is a good idea that this also propagates to the parent
> >> directory. What is a use case for this ?
> >
> > What do you think about this ?
> > I think it's no good idea. Until now you can rely on that whatever
> > happens in subdirectories doesn't modify variables in the parent
> > directory (the only way is to force something through the cache, which is
> > a bit ugly).
> > If you need to get information from a subdir to some other place, with
> > cmake 2.6 you can use a global property to do this, which will also work
> > over multiple levels of subdirectories. Doing this using PARENT_SCOPE
> > would require to build a chain of these calls through all directories,
> > which I think is not very nice and can require relatively much code.
> >
> > Do you have objections to removing that feature (propagating to the
> > parent directory) ?
>
> I am pretty sure raise_scope was removed in favor of this version of
> set, so if you remove it, there will be no way to raise scope...

I don't mean to remove the SET(PARENT_SCOPE) feature, where the main purpose 
is to set a global variable from within a function.
But if SET( ... PARENT_SCOPE) is called outside a function, the effect is that 
the variable is set in the parent directory. This is the part where I'm not 
sure it's a good idea.

Alex