[Haskell-cafe] Warning when attempting to install cabal-dev on the latest HP

Edward Amsden eca7215 at cs.rit.edu
Wed Jun 13 15:52:14 CEST 2012

For reference to anyone coming across this:

The issue is that cabal-dev does in fact depend on the old mtl, if one checks
the cabal file. (Thanks to dcoutts_ on #haskell).

The suggestion I received was to use virthualenv.

On Wed, Jun 13, 2012 at 9:20 AM, Edward Amsden <eca7215 at cs.rit.edu> wrote:
> http://hpaste.org/69885
> The warning in that paste occurs when I attempt
> $ cabal update
> $ cabal install cabal-dev
> This is curious because it wants to install a previous version of mtl.
> I can't figure out why. There doesn't seem to be any dependency
> between cabal-dev and mtl. According to hackage, the dependencies for
> cabal-dev are:
> cabal-dev -> (base, Cabal)
> Cabal -> (base, filepath)
> filepath -> (base)
> base -> ()
> The dependencies for mtl are (just to show no conflicts)
> mtl -> (base, transformers)
> transformers -> (base)
> base -> ()
> And there's not a versioning conflict with base.
> Why is cabal insisting on backdating mtl then?

Edward Amsden
Computer Science
Rochester Institute of Technology

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