[Haskell-cafe] cabal doens't forget old dependencies

[Sjoerd Visscher]

Ah, ok. I wasn't aware how flags work in Cabal, thanks.

Makes me wonder why that flag was turned off on hackage.
http://hackage.haskell.org/package/reactive-banana

On Jun 27, 2012, at 5:51 PM, Andres Löh wrote:

> Hi.
> 
>> I tried to install reactive-banana. This failed due to a dependency conflict, and then I noticed there was a newer version of reactive-banana. So I did cabal update, and tried to install again. But whatever I do, cabal keeps trying to install fclabels, but fclabels is no longer a dependency of reactive-banana-0.6.0.0! How can I let cabal forget this dependency?
> 
> From the reactive-banana Cabal file:
> 
>    if flag(UseExtensions)
>        extensions:     TypeFamilies, GADTs, MultiParamTypeClasses,
>                        BangPatterns, TupleSections,
>                        EmptyDataDecls
>        build-depends:  QuickCheck >= 1.2 && < 2.5,
>                        fclabels == 1.1.*,
>                        unordered-containers >= 0.2.1.0 && < 0.3,
>                        hashable == 1.1.*
>        CPP-options:    -DUseExtensions
> 
> So try "-f-UseExtensions" if you really want that?
> 
> Cheers,
>  Andres
> 
> 
> -- 
> Andres Löh, Haskell Consultant
> Well-Typed LLP, http://www.well-typed.com
> 

--
Sjoerd Visscher
https://github.com/sjoerdvisscher/blog