mpi

[Sean Farley]

Ryan Schmidt writes:

> On Sep 30, 2014, at 9:08 PM, Sean Farley wrote:
>
>> Ryan Schmidt writes:
>> 
>>>> The question, to me, is: why is it still not
>>>> possible to distinguish foo+gcc and foo+clang in MacPorts?
>>> 
>>> I'm not sure what you mean.
>> 
>> Why can't all a port's variants be installed at the same time?
>> 
>> $ port install boost
>> $ port install boost +gcc48
>> 
>> Every port could have its own custom prefix and only the active one
>> would be a symlink in /opt/local.
>
> That's not what variants are for. That's what subports are for.

Subports are trying to solve this but expose the implementation level
too far up. Only one solution should exist to depending on a
variant. Subports, unfortunately, put all the burden on the portfile
author and bloat the output of the list of ports.

$ port echo mpich*
mpich
mpich-clang
mpich-clang31
mpich-clang32
mpich-clang33
mpich-clang34
mpich-clang35
mpich-default
mpich-devel
mpich-devel-clang
mpich-devel-clang31
mpich-devel-clang32
mpich-devel-clang33
mpich-devel-clang34
mpich-devel-clang35
mpich-devel-default
mpich-devel-dragonegg31
mpich-devel-dragonegg32
mpich-devel-dragonegg33
mpich-devel-gcc43
mpich-devel-gcc44
mpich-devel-gcc45
mpich-devel-gcc46
mpich-devel-gcc47
mpich-devel-gcc48
mpich-devel-gcc49
mpich-devel-llvm
mpich-dragonegg31
mpich-dragonegg32
mpich-dragonegg33
mpich-gcc43
mpich-gcc44
mpich-gcc45
mpich-gcc46
mpich-gcc47
mpich-gcc48
mpich-gcc49
mpich-llvm

Why should this be exposed to the user? Imagine, now, if there were no
such thing as a variant. This would solve all the dependence issues on a
port's variant.