Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: Octree (user goal)
rejecting: Octree-0.5.4.2, 0.5.3, 0.5.2, 0.5.1, 0.5, 0.4, 0.3, 0.2.3, 0.2.2,
0.2.1, 0.2.0.1 (global constraint requires ==0.2)
trying: Octree-0.2
next goal: base (dependency of Octree-0.2)
rejecting: base-4.8.1.0/installed-4f7... (conflict: Octree => base<0)
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.