Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: music-preludes (user goal)
rejecting: music-preludes-1.9.0, music-preludes-1.8.1, music-preludes-1.8,
music-preludes-1.7.2, music-preludes-1.7.1 (constraint from user target
requires ==1.7)
trying: music-preludes-1.7
trying: contravariant-1.4 (dependency of adjunctions-4.3)
next goal: music-score (dependency of music-preludes-1.7)
rejecting: music-score-1.9.0, music-score-1.8.1, music-score-1.8,
music-score-1.7.2, music-score-1.7.1 (conflict: music-preludes =>
music-score==1.7)
rejecting: music-score-1.7 (conflict: contravariant==1.4, music-score =>
contravariant>=0.4.4 && <1)
rejecting: music-score-1.6.2, music-score-1.6.1, music-score-1.6,
music-score-1.3.1, music-score-1.3, music-score-1.2.2, music-score-1.2.1,
music-score-1.2 (conflict: music-preludes => music-score==1.7)
Backjump limit reached (currently 2000, change with --max-backjumps or try to
run with --reorder-goals).