Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: hprotoc (user goal)
rejecting: hprotoc-2.1.7, 2.1.6, 2.1.5, 2.1.4, 2.1.3, 2.1.2, 2.1.0, 2.0.17,
2.0.15, 2.0.14, 2.0.13, 2.0.12, 2.0.11, 2.0.10, 2.0.9, 2.0.7 (global
constraint requires ==2.0.6)
trying: hprotoc-2.0.6
trying: base-4.8.1.0/installed-4f7... (dependency of hprotoc-2.0.6)
next goal: parsec (dependency of hprotoc-2.0.6)
rejecting: parsec-3.1.9, 3.1.8, 3.1.7, 3.1.6, 3.1.5, 3.1.4, 3.1.3, 3.1.2,
3.1.1, 3.1.0, 3.0.1, 3.0.0 (conflict: hprotoc => parsec<3)
rejecting: parsec-2.1.0.1, 2.1.0.0, 2.0 (conflict:
base==4.8.1.0/installed-4f7..., parsec => base<4.8)
Dependency tree exhaustively searched.