Resolving dependencies...
cabal: Could not resolve dependencies:
trying: spline3-0.0.2 (user goal)
trying: tasty-quickcheck-0.8.3.2 (dependency of spline3-0.0.2)
trying: QuickCheck-2.8.1 (dependency of tasty-quickcheck-0.8.3.2)
trying: transformers-0.3.0.0/installed-16a... (dependency of QuickCheck-2.8.1)
trying: tasty-0.10.1.2 (dependency of spline3-0.0.2)
trying: optparse-applicative-0.11.0.2 (dependency of tasty-0.10.1.2)
trying: transformers-compat-0.4.0.4 (dependency of
optparse-applicative-0.11.0.2)
trying: transformers-compat-0.4.0.4:-two
rejecting: transformers-compat-0.4.0.4:-three (conflict:
transformers==0.3.0.0/installed-16a..., transformers-compat-0.4.0.4:three =>
transformers>=0.4.1 && <0.5)
rejecting: transformers-compat-0.4.0.4:+three (manual flag can only be changed
explicitly)
Backjump limit reached (change with --max-backjumps).