Cannot install Yorgey et al's “unbound” library with latest GHC/Haskell Platform

2
votes

Has anybody managed to get Yorgey et al's "unbound" library, for working with syntax with binding, to install with the latest GHC (7.0.3) and Haskell platform? Trying a cabal install unbound, I get the following:

Resolving dependencies...
cabal: cannot configure unbound-0.2.3. It requires base >=4.3 && <5
For the dependency on base >=4.3 && <5 there are these packages: base-4.3.0.0
and base-4.3.1.0. However none of them are available.
base-4.3.0.0 was excluded because of the top level dependency base -any
base-4.3.1.0 was excluded because of the top level dependency base -any

Anybody know a solution/work around, or what may be happening here?

1
haskellcabal
@Mikhail. Oops. Thanks, fixed. - Dominic Mulligan
'cabal install unbound' works for me on Linux with GHC 7.0.3 and Haskell Platform 2011.2.0.1. - Mikhail Glushenkov
@Mikhail Glushenkov. It appears that an older version of GHC was playing havoc with Cabal. After removing that version I managed to get the package to install correctly. - Dominic Mulligan

1 Answers

2
votes

Just to close this one:

  • The "unbound" library works fine with the 2011 Haskell Platform, and indeed, builds without warnings.

The OP had multiple (older) versions of GHC in his path, leading to build errors, since the package relies on GHC 7. Ensuring you have exactly the Haskell Platform environment is the solution.

As a note, we should write a script that checks the sanity of a given Haskell environment, to catch errors like this.