Resolving dependencies...
cabal: Could not resolve dependencies:
trying: pretty-1.1.3.3/installed-1.1... (dependency of pango-0.12.5.3)
next goal: semigroups (dependency of grapefruit-frp-0.1.0.5)
rejecting: semigroups-0.18.2, semigroups-0.18.1, semigroups-0.18.0.1,
semigroups-0.18, semigroups-0.17.0.1, semigroups-0.17, semigroups-0.16.2.2,
semigroups-0.16.2.1, semigroups-0.16.2, semigroups-0.16.1,
semigroups-0.16.0.1, semigroups-0.16 (conflict: grapefruit-frp =>
semigroups>=0.8 && <0.16)
trying: semigroups-0.15.4
trying: semigroups-0.15.4:+hashable
trying: semigroups-0.15.4:+unordered-containers
trying: semigroups-0.15.4:+text
rejecting: semigroups-0.15.4:+deepseq (conflict: pretty =>
deepseq==1.4.2.0/installed-1.4..., semigroups-0.15.4:deepseq => deepseq>=1.1
&& <1.4)
rejecting: semigroups-0.15.4:-deepseq (manual flag can only be changed
explicitly)
Backjump limit reached (currently 2000, change with --max-backjumps or try to
run with --reorder-goals).