* David Wheeler <[EMAIL PROTECTED]> [2004-07-17 18:24]: > On Jul 16, 2004, at 4:42 PM, A. Pagaltzis wrote: > > I don't think it can. Take the virtual package > > mail-transport-agent as an example, a dependency on which can > > be satisfied by exim, or postfix, or sendmail, or what have > > you. This works because all MTAs have a very similar > > interface. > > > > In other cases, a standard interface can be defined by Debian > > and wrapper scripts or some such can be written by the > > respective package maintainers. > > Yes, but this is up to the module developer, not to CPAN. If I > write my module so it can use either DBD::Pg or DBD::mysql, I > want to require users to install only one or the other, not > both. But whether it does work with both is my responsibility.
Yes, but what's your point? In fact you are arguing against virtual packages if the script only works with DBD::Pg or ::mysql, but not other DBDs -- because you'll need to depend on "::Pg or ::mysql" explicitly even if there was a virtual package for "any DBD". Obviously being able to list alternative dependencies is of more utility than the existence of virtual packages. Not only that, but the latter would also require changes to CPAN (how likely is that to happen?), whereas a list of alternative dependencies only requires a spec for its format and an implementation in EU::MM and/or Module::Builder. Regards, -- Aristotle "If you can't laugh at yourself, you don't take life seriously enough."
