Resolving dependencies... cabal: Could not resolve dependencies: trying: html-rules-0.1.0.1 (user goal) trying: mtl-2.2.1 (dependency of html-rules-0.1.0.1) next goal: transformers (dependency of html-rules-0.1.0.1) rejecting: transformers-0.5.2.0/installed-0.5..., transformers-0.5.2.0, transformers-0.5.1.0, transformers-0.5.0.1, transformers-0.5.0.0, transformers-0.4.3.0, transformers-0.4.2.0, transformers-0.4.1.0 (conflict: html-rules => transformers>=0.2 && <0.4) rejecting: transformers-0.3.0.0, transformers-0.2.2.1, transformers-0.2.1.0, transformers-0.2.0.0 (conflict: mtl => transformers>=0.4 && <0.6) rejecting: transformers-0.1.4.0, transformers-0.1.3.0, transformers-0.1.1.0, transformers-0.1.0.1, transformers-0.0.1.0, transformers-0.0.0.0, transformers-0.5.0.2, transformers-0.4.0.0 (conflict: html-rules => transformers>=0.2 && <0.4) rejecting: transformers-0.2.2.0 (conflict: mtl => transformers>=0.4 && <0.6) rejecting: transformers-0.1.0.0 (conflict: html-rules => transformers>=0.2 && <0.4) Dependency tree exhaustively searched.