[Haskell-cafe] Re: Rewriting a famous library and using the same name: pros and cons

[Ivan Lazar Miljenovic]

Jeremy Shaw <jeremy at n-heptane.com> writes:

> On Tue, Jun 8, 2010 at 7:06 PM, Ivan Lazar Miljenovic
> <ivan.miljenovic at gmail.com> wrote:
>
>> I recall having a discussion with either you or someone else from the
>> happstack team about why it isn't applicable there, but the QuickCheck
>> problem can be solved in the general case by having its dependency be a
>> compile-time-only option which is disabled by default.
>
> Not really. Cabal likes to recompile things, and it won't remember
> that I compiled another library with quickcheck enabled. So if library
> B depends on library A with quickcheck enabled, it may still happen
> that after I install library A with quickcheck enabled, cabal will
> decide to recompile A again  when building library B, and it will
> build A without quickcheck, causing B to fail...

You of course mean cabal-install, not Cabal when talking about
recompiling things (I know, I'm being picky, but still...).  Also, that
problem is the reason why I recognise that for happstack can't at the
moment have the QuickCheck dependency optional.

-- 
Ivan Lazar Miljenovic
Ivan.Miljenovic at gmail.com
IvanMiljenovic.wordpress.com