[xmonad] GroupNavigation build error

[Adam Vogt]

* On Wednesday, May 12 2010, Ivan Lazar Miljenovic wrote:

>Adam Vogt <vogt.adam at gmail.com> writes:
>> containers-0.3.0.0 should build with older GHCs. It would be much easier
>> to manage if we could just require a newer containers: maintaining those
>> macros is a fair amount of work. Is that allowed, or is it too great a
>> concern that this adds one more dependency to fetch for users with older
>> GHCs?
>
>It isn't: Cabal is the only library that comes with GHC that you should
>upgrade as otherwise you get diamond dependency problems (which is why
>"cabal upgrade" is currently disabled).

Well supposing that xmonad-core and xmonad-contrib are built with the
same containers version, and user's configs are compiled with -package
(which isn't done), keeping two versions can work, though there will be
issues to use say a Map produced by functions from another library
(though I don't believe this happens in user configs).

So maybe it could be made to work for most configs, but it looks like
conditional compilation (or just sticking to the containers-0.2 subset
of the api) will probably cause less trouble.

--
Adam