Type.Prelude

data OProxy (ordering :: Ordering)

Value proxy for Ordering types

Constructors

• OProxy

data LT :: Ordering

Instances

• IsOrdering LT
• AppendOrdering LT rhs LT
• InvertOrdering LT GT
• InvertOrdering GT LT

data GT :: Ordering

Instances

• IsOrdering GT
• AppendOrdering GT rhs GT
• InvertOrdering LT GT
• InvertOrdering GT LT

data EQ :: Ordering

Instances

• IsOrdering EQ
• AppendOrdering EQ rhs rhs
• InvertOrdering EQ EQ

class IsOrdering (ordering :: Ordering)  where

Class for reflecting a type level Ordering at the value level

Members

• reflectOrdering :: OProxy ordering -> Ordering

Instances

• IsOrdering LT
• IsOrdering EQ
• IsOrdering GT

reifyOrdering :: forall r. Ordering -> (forall o. IsOrdering o => OProxy o -> r) -> r

Use a value level Ordering as a type-level Ordering

data Ordering :: Type

data SProxy (sym :: Symbol)

A value-level proxy for a type-level symbol.

Constructors

• SProxy

class AppendSymbol (lhs :: Symbol) (rhs :: Symbol) (out :: Symbol) | lhs rhs -> out

Append two Symbol types together

class CompareSymbol (lhs :: Symbol) (rhs :: Symbol) (out :: Ordering) | lhs rhs -> out

Compare two Symbol types

class IsSymbol (sym :: Symbol)  where

A class for known symbols

Members

• reflectSymbol :: SProxy sym -> String

Instances

• (IsSymbol left, IsSymbol right) => IsSymbol (TypeConcat left right)

reifySymbol :: forall r. String -> (forall sym. IsSymbol sym => SProxy sym -> r) -> r

compareSymbol :: forall o r l. CompareSymbol l r o => SProxy l -> SProxy r -> OProxy o

appendSymbol :: forall o r l. AppendSymbol l r o => SProxy l -> SProxy r -> SProxy o

class TypeEquals a b | a -> b, b -> a where

This type class asserts that types a and b are equal.

The functional dependencies and the single instance below will force the two type arguments to unify when either one is known.

Note: any instance will necessarily overlap with refl below, so instances of this class should not be defined in libraries.

Members

• to :: a -> b
• from :: b -> a

Instances

• TypeEquals a a

data Proxy a

Value proxy for kind Type types.

Constructors

• Proxy