I am writing a Portfile and i would appreciate help

[Andrea Cimino]

I am writing a Portfile for the "Parma Polyhedra Library" project 
(http://www.cs.unipr.it/ppl)
but i have some questions for you, developers.

You can find a first snapshot of the Portfile here:
http://www.cs.unipr.it/cgi-bin/viewvc/viewvc.cgi/ppl/DarwinPorts_Portfile?revision=1.1.2.1&view=markup&pathrev=ppl-0_9-branch 


This is my first Portfile so i don't expect that meets the MacPorts 
standards, here the questions:

1) Is really needed to have a ppl-dev package, with headers and so on? 
Or we can just provide a 'ppl' package with everything installed there?
2) The 'ppl' provides several Prolog interfaces so i decided to write 
some variants: is this the right way to help MacPorts users installing 
the 'ppl' and building the interfaces?
3) The 'ppl', depending on the presence of the 'glpk' library, builds 
the optional tool 'ppl_lpsol'. The glpk dependency should be declared in 
a variant or in the main section of the Portfile?

Other suggestions obviously are welcome!

Best regards,
Andrea Cimino