[pacman-dev] Alternative dependencies.

[Xyne]

Hi,

Would it be possible to implement support for alternative dependencies, e.g. a
package that could use either wget or curl to handle downloads?

I'm not asking for this to be implemented. I'm just asking whether there are
any technical limitations to such an approach.

I know that "provides" can be used to do this, e.g. openjdk6 and jre both
provide java-runtime to satisfy that dependency in other packages. The approach
is limited though. Using the example above, we couldn't simply add
"provides=('download-client')" to both curl and wget because they are not
interchangeable.

The basic usage case is when an application is capable of detecting any one of
a number of different external apps that it can use to satisfy a given
dependency. There is currently no way to depend on "at least one" of those.

I can imagine a very simple syntax for this too, e.g. "depends=('curl ||
wget')" so the question is whether the dependency-handling mechanism could be
adapted to check for alternatives. If none are found, it could probably use the
upcoming "provides" selection dialogue to allow the user to choose the desired
dependency.

So, would that be possible?
Also, would that be acceptable?

Again, I'm not asking anyone to do this. I'm just inquiring about the
possibility.

Regards,
Xyne