Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: dataenc (user goal)
rejecting: dataenc-0.14.0.7, dataenc-0.14.0.6, dataenc-0.14.0.5,
dataenc-0.14.0.4, dataenc-0.14.0.3, dataenc-0.14.0.2, dataenc-0.14,
dataenc-0.13.0.5, dataenc-0.13.0.4, dataenc-0.13.0.3, dataenc-0.13.0.2,
dataenc-0.13.0.1, dataenc-0.13.0.0 (constraint from user target requires
==0.12.1.0)
trying: dataenc-0.12.1.0
next goal: base (dependency of dataenc-0.12.1.0)
rejecting: base-4.9.0.0/installed-4.9... (conflict: dataenc => base>=4.0.0 &&
<4.1)
rejecting: base-4.9.0.0, base-4.8.2.0, base-4.8.1.0, base-4.8.0.0,
base-4.7.0.2, base-4.7.0.1, base-4.7.0.0, base-4.6.0.1, base-4.6.0.0,
base-4.5.1.0, base-4.5.0.0, base-4.4.1.0, base-4.4.0.0, base-4.3.1.0,
base-4.3.0.0, base-4.2.0.2, base-4.2.0.1, base-4.2.0.0, base-4.1.0.0,
base-4.0.0.0, base-3.0.3.2, base-3.0.3.1 (constraint from non-upgradeable
package requires installed instance)
Dependency tree exhaustively searched.