Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
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Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: rings-0.1.1 (user goal)
[__1] next goal: semigroupoids (dependency of rings)
[__1] rejecting: semigroupoids-5.3.4, semigroupoids-5.3.3,
semigroupoids-5.3.2, semigroupoids-5.3.1, semigroupoids-5.2.2,
semigroupoids-5.2.1, semigroupoids-5.2, semigroupoids-5.1,
semigroupoids-5.0.1, semigroupoids-5.0.0.4, semigroupoids-5.0.0.3,
semigroupoids-5.0.0.2, semigroupoids-5.0.0.1, semigroupoids-5,
semigroupoids-4.3, semigroupoids-4.2, semigroupoids-4.0.4,
semigroupoids-4.0.3, semigroupoids-4.0.2.1, semigroupoids-4.0.2,
semigroupoids-4.0.1, semigroupoids-4.0, semigroupoids-3.1,
semigroupoids-3.0.3, semigroupoids-3.0.2, semigroupoids-3.0.1,
semigroupoids-3.0.0.2, semigroupoids-3.0.0.1, semigroupoids-3.0,
semigroupoids-1.3.4, semigroupoids-1.3.3, semigroupoids-1.3.2.1,
semigroupoids-1.3.2, semigroupoids-1.3.1.2, semigroupoids-1.3.1.1,
semigroupoids-1.3.1, semigroupoids-1.3, semigroupoids-1.2.6.2,
semigroupoids-1.2.6.1, semigroupoids-1.2.6, semigroupoids-1.2.5,
semigroupoids-1.2.4, semigroupoids-1.2.2.4, semigroupoids-1.2.2.3,
semigroupoids-1.2.2.2, semigroupoids-1.2.2.1, semigroupoids-1.2.2,
semigroupoids-1.2.1, semigroupoids-1.2.0, semigroupoids-1.1.3,
semigroupoids-1.1.2, semigroupoids-1.1.1, semigroupoids-1.1.0,
semigroupoids-1.0.0, semigroupoids-5.3, semigroupoids-4.5 (conflict: rings =>
semigroupoids>=0.5 && <1.0)
[__1] fail (backjumping, conflict set: rings, semigroupoids)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: rings, semigroupoids