[Haskell-cafe] trying to cabal install lambdabot, failure on 'random' package

[Daniel Fischer]

On Sunday 08 May 2011 09:24:50, Sean Perry wrote:
> package random-1.0.0.3 requires time-1.2.0.3
> package random-1.0.0.3 requires time-1.2.0.4
> Preprocessing library show-0.4.1.1...
> Building show-0.4.1.1...
> <command line>: cannot satisfy -package-id
> random-1.0.0.3-749b78c54a8a99991b32dbb45d98a91b: 
> random-1.0.0.3-749b78c54a8a99991b32dbb45d98a91b is shadowed by package
> random-1.0.0.3-57524486875e0c4c260dd22788921013

You have two versions(?) of random-1.0.0.3, one in the global package-db, 
one in the user-db. The one in the user-db shadows the global, making it 
unusable. That's BAD. Having boot packages (random, process, directory, 
time, ...) in both, global and user db, tends to break stuff, check what's 
broken already with

$ ghc-pkg check

If too much is broken, delete your user-db and reinstall fresh, otherwise 
try unregistering the ones in the user-db shadowing stuff in the global db, 
in particular random-1.0.0.3,

$ ghc-pkg unregister --user random-1.0.0.3

It will probably notify you that unregistering that will break a couple of 
other packages, the best would probably be to unregister those too and 
rebuild them against the global random.