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
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

For more information, see: https://wiki.haskell.org/Cabal/NewBuild

Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: registry-hedgehog-0.2.0.1 (user goal)
[__1] next goal: tasty-hedgehog (dependency of registry-hedgehog)
[__1] rejecting: tasty-hedgehog-1.0.0.1, tasty-hedgehog-1.0.0.0,
tasty-hedgehog-0.2.0.0, tasty-hedgehog-0.1.0.2, tasty-hedgehog-0.1.0.1,
tasty-hedgehog-0.1.0.0 (conflict: registry-hedgehog => tasty-hedgehog>=0.3 &&
<0.4)
[__1] fail (backjumping, conflict set: registry-hedgehog, tasty-hedgehog)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: registry-hedgehog, tasty-hedgehog