Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: hatt (user goal)
rejecting: hatt-1.5.0.3, hatt-1.5.0.2, hatt-1.5.0.0, hatt-1.4.0.2,
hatt-1.4.0.1, hatt-1.4.0, hatt-1.3.1, hatt-1.3.0, hatt-1.2.1, hatt-1.2.0,
hatt-1.1.1, hatt-1.1, hatt-1.0, hatt-0.3, hatt-0.2 (constraint from user
target requires ==0.1)
trying: hatt-0.1
next goal: base (dependency of hatt-0.1)
rejecting: base-4.9.0.0/installed-4.9... (conflict: hatt => base>=4.2 && <4.3)
rejecting: base-4.9.0.0, base-4.8.2.0, base-4.8.1.0, base-4.8.0.0,
base-4.7.0.2, base-4.7.0.1, base-4.7.0.0, base-4.6.0.1, base-4.6.0.0,
base-4.5.1.0, base-4.5.0.0, base-4.4.1.0, base-4.4.0.0, base-4.3.1.0,
base-4.3.0.0, base-4.2.0.2, base-4.2.0.1, base-4.2.0.0, base-4.1.0.0,
base-4.0.0.0, base-3.0.3.2, base-3.0.3.1 (constraint from non-upgradeable
package requires installed instance)
Dependency tree exhaustively searched.