Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: parallel-io (user goal)
rejecting: parallel-io-0.3.3, 0.3.2.2, 0.3.2.1, 0.3.2, 0.3.1, 0.3.0.2,
0.3.0.1, 0.3.0, 0.2.2, 0.2.1.1, 0.2.1 (global constraint requires ==0.2)
trying: parallel-io-0.2
next goal: base (dependency of parallel-io-0.2)
rejecting: base-4.7.0.1/installed-e4b... (conflict: parallel-io => base<0)
rejecting: base-4.8.0.0, 4.7.0.2, 4.7.0.1, 4.7.0.0, 4.6.0.1, 4.6.0.0, 4.5.1.0,
4.5.0.0, 4.4.1.0, 4.4.0.0, 4.3.1.0, 4.3.0.0, 4.2.0.2, 4.2.0.1, 4.2.0.0,
4.1.0.0, 4.0.0.0, 3.0.3.2, 3.0.3.1 (global constraint requires installed
instance)
Dependency tree exhaustively searched.