setting variants on the fly

[Rainer Müller]

Markus Weissmann wrote:
> What would be _very_ cool to solve this problem would be something
> Landon Fuller suggested: Some kind of inheritance for Portfiles.
> Then we could do a gtk2 port with a description, version, hashes, etc.
> and do a gtk2-quartz port which inherits from gtk2 but changes some
> directories (for avoiding file conflicts with gtk2) and some options (to
> enable quartz). If version X won't work for the inheriting port, it may
> overwrite the version key and the checksums.

Yes, the idea of multiple Portfiles per port was already brought up some
time ago. This would also allow us to get rid of separate devel ports.
At the moment they are rather useless for testing, because all
dependencies would need to be on $foo-devel instead of the regular $foo.

I the case of gtk2, I don't think it is a good idea to give the ports
different names, because that will lead to problems with dependencies.
For example, gtk2 and gtk2-quartz would be mutual exclusive and
therefore you can only install one of them. It would be way better for
specifying dependencies if both versions are available with the same
name gtk2. Then the user could decide either to use quartz or not for
dependents without changes needed on these port.

With multiple Portfiles per port one could install the devel version for
testing and link all dependencies which specify the regular port name
with it. We would have better testing possibilities without the need for
a unstable/stable tree separation.

Regards,
Rainer