Resolving dependencies...
cabal: Could not resolve dependencies:
trying: base-4.9.0.0/installed-4.9... (dependency of progression-0.4)
next goal: haskeline (dependency of progression-0.4)
rejecting: haskeline-0.7.2.3/installed-0.7..., haskeline-0.7.2.3,
haskeline-0.7.2.2, haskeline-0.7.2.1, haskeline-0.7.2.0, haskeline-0.7.1.3,
haskeline-0.7.1.2, haskeline-0.7.1.1, haskeline-0.7.1.0, haskeline-0.7.0.3,
haskeline-0.7.0.2, haskeline-0.7.0.1, haskeline-0.7.0.0 (conflict: progression
=> haskeline>=0.6 && <0.7)
rejecting: haskeline-0.6.4.7, haskeline-0.6.4.6 (conflict:
base==4.9.0.0/installed-4.9..., haskeline => base==2.* || >=4.1 && <4.6)
rejecting: haskeline-0.6.4.5, haskeline-0.6.4.4, haskeline-0.6.4.3,
haskeline-0.6.4.2, haskeline-0.6.4.1 (conflict:
base==4.9.0.0/installed-4.9..., haskeline => base==2.* || >=4.1 && <4.5)
rejecting: haskeline-0.6.4.0, haskeline-0.6.3.2, haskeline-0.6.3.1,
haskeline-0.6.3, haskeline-0.6.2.4, haskeline-0.6.2.3 (conflict:
base==4.9.0.0/installed-4.9..., haskeline => base==2.* || >=4.1 && <4.4)
rejecting: haskeline-0.6.2.2, haskeline-0.6.2.1, haskeline-0.6.2 (conflict:
base==4.9.0.0/installed-4.9..., haskeline => base==2.* || >=4.1 && <4.3)
trying: haskeline-0.6.1.6
next goal: unix (dependency of haskeline-0.6.1.6)
rejecting: unix-2.7.2.0/installed-2.7..., unix-2.7.2.1, unix-2.7.2.0,
unix-2.7.1.0, unix-2.7.0.1, unix-2.7.0.0, unix-2.6.0.1, unix-2.6.0.0,
unix-2.5.1.1, unix-2.5.1.0, unix-2.5.0.0, unix-2.4.2.0, unix-2.4.1.0,
unix-2.4.0.2, unix-2.4.0.1, unix-2.4.0.0 (conflict: haskeline => unix>=2.0 &&
<2.4)
rejecting: unix-2.3.2.0, unix-2.3.1.0, unix-2.3.0.0, unix-2.2.0.0, unix-2.0
(conflict: base==4.9.0.0/installed-4.9..., unix => base<4.3)
Dependency tree exhaustively searched.