Type.Family.Constraint

Reexports the kind Constraint, as well as some conveniences for working with Constraints.

Documentation

type ØC = (() :: Constraint)

The empty Constraint.

type Fail = True ~ False

class IffC b t f => Iff b t f

Associated Types

type IffC b t f :: Constraint

Instances

f => Iff False t f

Associated Types

type IffC (False :: Bool) (t :: Constraint) (f :: Constraint) :: Constraint

t => Iff True t f

Associated Types

type IffC (True :: Bool) (t :: Constraint) (f :: Constraint) :: Constraint

class d (c a) => Comp d c a

Instances

d (c a) => Comp k l d c a

data Constraint :: *

The kind of constraints, like Show a

Instances

Category Constraint (:-)

Methods

id :: cat a a

(.) :: cat b c -> cat a b -> cat a c

c => Known Constraint Wit c

If the constraint c holds, there is a canonical construction for a term of type Wit c, viz. the constructor Wit.

Associated Types

type KnownC Wit (c :: Wit -> *) (a :: Wit) :: Constraint

Methods

known :: c a

type KnownC Constraint Wit c

type KnownC Constraint Wit c = c