Resolving dependencies...
Error: cabal: Could not resolve dependencies:
[__0] trying: MultipletCombiner-0.0.1 (user goal)
[__1] next goal: base (dependency of MultipletCombiner)
[__1] rejecting: base-4.16.3.0/installed-4.16.3.0 (conflict: MultipletCombiner
=> base>=4.15 && <4.16)
[__1] skipping: base-4.18.0.0, base-4.17.1.0, base-4.17.0.0, base-4.16.4.0,
base-4.16.3.0, base-4.16.2.0, base-4.16.1.0, base-4.16.0.0 (has the same
characteristics that caused the previous version to fail: excluded by
constraint '>=4.15 && <4.16' from 'MultipletCombiner')
[__1] rejecting: base-4.15.1.0, base-4.15.0.0, base-4.14.3.0, base-4.14.2.0,
base-4.14.1.0, base-4.14.0.0, base-4.13.0.0, base-4.12.0.0, base-4.11.1.0,
base-4.11.0.0, base-4.10.1.0, base-4.10.0.0, base-4.9.1.0, 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)
[__1] fail (backjumping, conflict set: MultipletCombiner, base)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: base, MultipletCombiner