Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: darcs (user goal)
rejecting: darcs-2.10.2, 2.10.1, 2.10.0, 2.8.5, 2.8.4, 2.8.3, 2.8.2, 2.8.1,
2.8.0, 2.5.2, 2.5.1, 2.5, 2.4.4, 2.4.3, 2.4.1, 2.4, 2.3.1, 2.3.0, 2.2.1,
2.2.0, 2.1.99.0, 2.1.98.2 (global constraint requires ==2.1.2.2)
trying: darcs-2.1.2.2
next goal: base (dependency of darcs-2.1.2.2)
rejecting: base-4.8.1.0/installed-4f7... (conflict: darcs => base<4)
rejecting: base-4.8.1.0, 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.