Yes, that was my conclusion as well. It would seem the problem is really just because (in this case) we have org and org-plus-contrib as two packages in the org/elpa repos when really here should just be org and org-contrib. This would then mean if you have a package which depends on org, all is good and if you want the contrib stuff, you just install an additional package with just the contrib additions.  Would also make things easier with 'helpers' like use-package. 

Tim


On 5 March 2017 at 08:57, Mark Oteiza <mvoteiza@udel.edu> wrote:
Tim Cross <theophilusx@gmail.com> writes:

> Is there a way to specify alternative dependencies in a package?
>
> Situation: installing a package is resulting in an additional package being installed
> even though the dependencies for the package have already been satisfied by another
> package. This results in two packages being installed which provide overlapping
> functionality.
>
> Example. I have installed org-plus-contrib. I then install elfeed-org, which has a
> dependency on org. This results in the org package being installed, but org is
> already installed as part of the org-plus-contrib package.
>
> I'm trying to work out if this is a problem with how dependencies are defined in the
> elfeed-org package or is it a problem with how org-plus-conrib is specifying what
> dependency it satisfies? Need to know in order to determine where this issue needs to
> be logged.

IIUC, package.el figures out dependencies by package name, not by the
features it provides.  So, I think the answer to your question is no.



--
regards,

Tim

--
Tim Cross