wiki:KindAnnotations

Version 2 (modified by malcolm.wallace@…, 9 years ago) (diff)

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Kind Annotations

Ghc permits type expressions (or is it only type variables?) to be annotated with a kind signature. See this section of the ghc user guide.

type T (f :: * -> *) = f Int

Pros

  • Without the ability to write a kind signature, there are cases where one must introduce dummy data constructors purely for their effect in forcing a higher-kindedness on a type variable.

Cons

  • con

Proposal

To adopt explicit kind annotations as part of the language, more or less exactly as ghc permits. Ticket: #84