Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: intervals (user goal)
rejecting: intervals-0.7.1, 0.7.0.1, 0.7, 0.6, 0.5.1.1, 0.5.1, 0.5, 0.4.2,
0.4.1, 0.4, 0.3, 0.2.2.1, 0.2.2, 0.2.1.1, 0.2.1, 0.2.0.3, 0.2.0.2, 0.2.0.1
(global constraint requires ==0.2.0)
trying: intervals-0.2.0
trying: base-4.8.1.0/installed-4f7... (dependency of intervals-0.2.0)
next goal: array (dependency of intervals-0.2.0)
rejecting: array-0.5.1.0/installed-d42..., 0.5.1.0, 0.5.0.0, 0.4.0.1, 0.4.0.0
(conflict: intervals => array>=0.3.0 && <0.4)
rejecting: array-0.3.0.3 (conflict: base==4.8.1.0/installed-4f7..., array =>
base>=4.2 && <4.5)
rejecting: array-0.3.0.2, 0.3.0.1 (conflict: base==4.8.1.0/installed-4f7...,
array => base>=4.2 && <4.4)
rejecting: array-0.3.0.0 (conflict: base==4.8.1.0/installed-4f7..., array =>
base>=3 && <4.4)
rejecting: array-0.2.0.0, 0.1.0.0 (conflict: intervals => array>=0.3.0 &&
<0.4)
Dependency tree exhaustively searched.