Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: hat (user goal)
rejecting: hat-2.9.0.0, 2.8.0.0, 2.7.0.12, 2.7.0.11, 2.7.0.10, 2.7.0.9,
2.7.0.8, 2.7.0.7, 2.7.0.6, 2.7.0.5, 2.7.0.4 (global constraint requires
==2.7.0.3)
trying: hat-2.7.0.3
trying: base-4.8.1.0/installed-4f7... (dependency of hat-2.7.0.3)
next goal: haskeline (dependency of hat-2.7.0.3)
rejecting: haskeline-0.7.2.1/installed-0a4..., 0.7.2.1, 0.7.2.0, 0.7.1.3,
0.7.1.2, 0.7.1.1, 0.7.1.0, 0.7.0.3, 0.7.0.2, 0.7.0.1, 0.7.0.0 (conflict: hat
=> haskeline==0.6.*)
trying: haskeline-0.6.4.7
next goal: unix (dependency of haskeline-0.6.4.7)
rejecting: unix-2.7.1.0/installed-643..., 2.7.1.0, 2.7.0.1, 2.7.0.0, 2.6.0.1,
2.6.0.0 (conflict: haskeline => unix>=2.0 && <2.6)
rejecting: unix-2.5.1.1, 2.5.1.0 (conflict: base==4.8.1.0/installed-4f7...,
unix => base>=4.5 && <4.6)
rejecting: unix-2.5.0.0 (conflict: base==4.8.1.0/installed-4f7..., unix =>
base>=4.2 && <4.5)
rejecting: unix-2.4.2.0, 2.4.1.0 (conflict: base==4.8.1.0/installed-4f7...,
unix => base>=4.2 && <4.4)
rejecting: unix-2.4.0.2, 2.4.0.1 (conflict: base==4.8.1.0/installed-4f7...,
unix => base>=4.2 && <4.3)
rejecting: unix-2.4.0.0 (conflict: base==4.8.1.0/installed-4f7..., unix =>
base>=4.1 && <4.3)
rejecting: unix-2.3.2.0, 2.3.1.0, 2.3.0.0, 2.2.0.0, 2.0 (conflict:
base==4.8.1.0/installed-4f7..., unix => base<4.3)
Dependency tree exhaustively searched.