Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: yi (user goal)
rejecting: yi-0.12.2, 0.12.1, 0.12.0, 0.11.2, 0.11.1, 0.11.0, 0.10.1, 0.10.0,
0.8.2, 0.8.1, 0.8.0, 0.7.2, 0.7.1, 0.7.0, 0.6.7.0, 0.6.6.0, 0.6.5.0, 0.6.4.0,
0.6.3.0, 0.6.2.4, 0.6.2.3, 0.6.2.2, 0.6.1, 0.6.0, 0.5.2, 0.5.0.1, 0.4.6.2,
0.4.6 (global constraint requires ==0.4.3)
trying: yi-0.4.3
trying: base-4.8.1.0/installed-4f7... (dependency of yi-0.4.3)
next goal: parsec (dependency of yi-0.4.3)
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: yi => parsec>=2.1 && <2.2)
rejecting: parsec-2.1.0.1, 2.1.0.0 (conflict: base==4.8.1.0/installed-4f7...,
parsec => base<4.8)
rejecting: parsec-2.0 (conflict: yi => parsec>=2.1 && <2.2)
Dependency tree exhaustively searched.