Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] next goal: transformers-compat (user goal)
[__0] rejecting: transformers-compat-0.6.6, transformers-compat-0.6.5,
transformers-compat-0.6.4, transformers-compat-0.6.2,
transformers-compat-0.6.1.6, transformers-compat-0.6.1.5,
transformers-compat-0.6.1.4 (constraint from user target requires ==0.6.1.3)
[__0] trying: transformers-compat-0.6.1.3
[__1] trying: transformers-compat:-five
[__2] trying: transformers-compat:-four
[__3] trying: transformers-compat:+three
[__4] next goal: transformers (dependency of transformers-compat +/-five
+/-four +/-three +/-two)
[__4] rejecting: transformers-0.5.6.2/installed-0.5.6.2, transformers-0.5.6.2,
transformers-0.5.5.2, transformers-0.5.5.0, transformers-0.5.4.0 (conflict:
transformers-compat -five -four +three => transformers>=0.3 && <0.4)
[__4] rejecting: transformers-0.5.2.0, transformers-0.5.1.0,
transformers-0.5.0.1, transformers-0.5.0.0 (conflict: transformers-compat
-five +/-four +/-three +/-two => transformers>=0.2 && <0.4 || >=0.4.1 && <0.5
|| >=0.5.3 && <0.6)
[__4] rejecting: transformers-0.4.3.0, transformers-0.4.2.0,
transformers-0.4.1.0 (conflict: transformers-compat -five -four +/-three
+/-two => transformers>=0.2 && <0.4 || >=0.5.3 && <0.6)
[__4] trying: transformers-0.3.0.0
[__5] next goal: base (dependency of transformers-compat)
[__5] rejecting: base-4.14.1.0/installed-4.14.1.0 (conflict: transformers
+/-applicativeinbase => base>=1.0 && <4.8)
[__5] rejecting: base-4.15.0.0, base-4.14.1.0, base-4.14.0.0, base-4.13.0.0,
base-4.12.0.0, base-4.11.1.0, base-4.11.0.0, base-4.10.1.0, base-4.10.0.0,
base-4.9.1.0, base-4.9.0.0, base-4.8.2.0, base-4.8.1.0, base-4.8.0.0,
base-4.7.0.2, base-4.7.0.1, base-4.7.0.0, base-4.6.0.1, base-4.6.0.0,
base-4.5.1.0, base-4.5.0.0, base-4.4.1.0, base-4.4.0.0, base-4.3.1.0,
base-4.3.0.0, base-4.2.0.2, base-4.2.0.1, base-4.2.0.0, base-4.1.0.0,
base-4.0.0.0, base-3.0.3.2, base-3.0.3.1 (constraint from non-upgradeable
package requires installed instance)
[__5] fail (backjumping, conflict set: base, transformers,
transformers-compat)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: transformers-compat, base,
transformers, transformers-compat:five, transformers-compat:four,
transformers-compat:three
Try running with --minimize-conflict-set to improve the error message.