@hackage exists0.1

Existential datatypes holding evidence of constraints

This package contains:

  • Existential datatypes for holding evidence of constraints on types of kind * and * -> *;

  • Type classes for existential datatypes holding evidence of constraints on types of kind * and * -> *;

  • Completely useless existential datatypes holding evidence of no constraint on types of kind * and * -> *;

  • Assorted type class instances for the above;

  • A type-level combinator for combining constraint constructors.

Some of these should maybe be split off into separate packages.

Data.Exists is the important module, the rest are peripheral.