Resolving dependencies...
cabal: Could not resolve dependencies:
trying: hfd-0.0.2 (user goal)
trying: MissingH-1.3.0.1 (dependency of hfd-0.0.2)
trying: mtl-2.2.1 (dependency of MissingH-1.3.0.1)
next goal: transformers (dependency of hfd-0.0.2)
rejecting: transformers-0.4.2.0/installed-21d..., 0.4.3.0, 0.4.2.0, 0.4.1.0,
0.3.0.0 (conflict: hfd => transformers<0.3.0.0)
rejecting: transformers-0.2.2.1, 0.2.2.0, 0.2.1.0, 0.2.0.0, 0.1.4.0, 0.1.3.0,
0.1.1.0, 0.1.0.1, 0.1.0.0, 0.0.1.0, 0.0.0.0 (conflict: mtl =>
transformers==0.4.*)
rejecting: transformers-0.4.0.0 (conflict: hfd => transformers<0.3.0.0)
Backjump limit reached (change with --max-backjumps).