Resolving dependencies... cabal: Could not resolve dependencies: next goal: pandoc (user goal) rejecting: pandoc-1.18, pandoc-1.17.2, pandoc-1.17.1, pandoc-1.17.0.3, pandoc-1.17.0.2, pandoc-1.17.0.1, pandoc-1.17, pandoc-1.16.0.2, pandoc-1.16.0.1, pandoc-1.16, pandoc-1.15.2.1 (constraint from user target requires ==1.15.2) trying: pandoc-1.15.2 trying: base-4.9.0.0/installed-4.9... (dependency of pandoc-1.15.2) next goal: cmark (dependency of pandoc-1.15.2) rejecting: cmark-0.5.4, cmark-0.5.3.1, cmark-0.5.2.1, cmark-0.5.2, cmark-0.5.1, cmark-0.5.0 (conflict: pandoc => cmark>=0.4.0.1 && <0.5) rejecting: cmark-0.4.1, cmark-0.4.0.1 (conflict: base==4.9.0.0/installed-4.9..., cmark => base>=4.5 && <4.9) rejecting: cmark-0.3.4, cmark-0.3.3.1, cmark-0.3.3, cmark-0.3.2, cmark-0.3.1, cmark-0.3.0.1, cmark-0.3, cmark-0.2.0.2, cmark-0.2.0.1, cmark-0.2, cmark-0.1.0.1, cmark-0.1.0.0, cmark-0.5.3, cmark-0.3.5 (conflict: pandoc => cmark>=0.4.0.1 && <0.5) Dependency tree exhaustively searched.