Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: computational-algebra (user goal)
rejecting: computational-algebra-0.3.0.0, computational-algebra-0.2.0.0,
computational-algebra-0.1.3.6, computational-algebra-0.1.3.5,
computational-algebra-0.1.3.1 (constraint from user target requires ==0.1.3.0)
trying: computational-algebra-0.1.3.0
trying: base-4.9.0.0/installed-4.9... (dependency of
computational-algebra-0.1.3.0)
next goal: heaps (dependency of computational-algebra-0.1.3.0)
rejecting: heaps-0.3.3, heaps-0.3.2.1, heaps-0.3.2, heaps-0.3.1, heaps-0.3.0.1
(conflict: computational-algebra => heaps==0.2.*)
rejecting: heaps-0.2.3, heaps-0.2.2, heaps-0.2.1.1, heaps-0.2 (conflict:
base==4.9.0.0/installed-4.9..., heaps => base>=4 && <4.8)
rejecting: heaps-0.1 (conflict: computational-algebra => heaps==0.2.*)
Dependency tree exhaustively searched.