< -package:ghc-lib-parser is:exact

Comparison (<) of comparable types, as a constraint.
"Smaller than". Type-level version of (<).

Example

>>> :kind! Eval ("a" < "b")
Eval ("a" < "b") :: Bool
= 'True
Proof that the first argument is strictly less than the second argument.
Less-than relation relation. Defined in terms of <= and /=.