Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: syntax-example (user goal)
rejecting: syntax-example-1.0.0.0 (constraint from user target requires
==0.4.0.0)
trying: syntax-example-0.4.0.0
trying: base-4.9.0.0/installed-4.9... (dependency of syntax-example-0.4.0.0)
next goal: syntax-printer (dependency of syntax-example-0.4.0.0)
rejecting: syntax-printer-1.0.0.0, syntax-printer-0.1.0.0 (conflict:
base==4.9.0.0/installed-4.9..., syntax-printer => base>=4.7 && <4.8)
Dependency tree exhaustively searched.