Resolving dependencies...
cabal: Could not resolve dependencies:
trying: sylvia-0.2.2 (user goal)
trying: base-4.8.1.0/installed-4f7... (dependency of sylvia-0.2.2)
next goal: void (dependency of sylvia-0.2.2)
rejecting: void-0.7.1, 0.7, 0.6.1, 0.6 (conflict: sylvia => void>=0.5.5 &&
<0.6)
rejecting: void-0.5.12, 0.5.11, 0.5.10, 0.5.8, 0.5.7, 0.5.6, 0.5.5.1, 0.5.5
(conflict: base==4.8.1.0/installed-4f7..., void => base>=3 && <4.8)
rejecting: void-0.5.4.3, 0.5.4.2, 0.5.4.1, 0.5.4, 0.5.3, 0.5.2, 0.5.1, 0.5.0,
0.4, 0.3, 0.2, 0.1 (conflict: sylvia => void>=0.5.5 && <0.6)
Dependency tree exhaustively searched.