Resolving dependencies...
cabal: Could not resolve dependencies:
trying: blakesum-demo-0.5 (user goal)
trying: base-4.7.0.1/installed-e4b... (dependency of blakesum-demo-0.5)
next goal: haskell98 (dependency of blakesum-demo-0.5)
rejecting: haskell98-2.0.0.3/installed-85b..., 2.0.0.3, 2.0.0.2, 2.0.0.1,
2.0.0.0 (conflict: blakesum-demo => haskell98>=1 && <2)
rejecting: haskell98-1.1.0.1, 1.1.0.0, 1.0.1.1 (conflict:
base==4.7.0.1/installed-e4b..., haskell98 => base>=3 && <4.6)
rejecting: haskell98-1.0.1.0 (conflict: base==4.7.0.1/installed-e4b...,
haskell98 => base<4.6)
rejecting: haskell98-1.0 (conflict: base==4.7.0.1/installed-e4b..., haskell98
=> base<4.3)
Dependency tree exhaustively searched.