Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: happindicator (user goal)
rejecting: happindicator-0.0.4, happindicator-0.0.3 (constraint from user
target requires ==0.0.2)
rejecting: happindicator-0.0.2 (conflict: requires pkg-config package
appindicator-0.1-any, not found in the pkg-config database)
rejecting: happindicator-0.0.1 (constraint from user target requires ==0.0.2)
Dependency tree exhaustively searched.