W3cubDocs

/Haskell 9

Data.Type.Ord

License BSD-style (see the LICENSE file in the distribution)
Maintainer [email protected]
Stability stable
Portability not portable
Safe Haskell Safe
Language Haskell2010

Description

Basic operations on type-level Orderings.

Since: base-4.16.0.0

type family Compare (a :: k) (b :: k) :: Ordering Source

Compare branches on the kind of its arguments to either compare by Symbol or Nat.

Since: base-4.16.0.0

Instances
Instances details
type Compare (a :: Natural) (b :: Natural) Source
Instance details

Defined in GHC.Internal.Data.Type.Ord

type Compare (a :: Natural) (b :: Natural) = CmpNat a b
type Compare (a :: Char) (b :: Char) Source
Instance details

Defined in GHC.Internal.Data.Type.Ord

type Compare (a :: Char) (b :: Char) = CmpChar a b
type Compare (a :: Symbol) (b :: Symbol) Source
Instance details

Defined in GHC.Internal.Data.Type.Ord

type Compare (a :: Symbol) (b :: Symbol) = CmpSymbol a b

data OrderingI (a :: k) (b :: k) where Source

Ordering data type for type literals that provides proof of their ordering.

Since: base-4.16.0.0

Constructors

LTI :: forall {k} (a :: k) (b :: k). Compare a b ~ 'LT => OrderingI a b
EQI :: forall {k} (a :: k). Compare a a ~ 'EQ => OrderingI a a
GTI :: forall {k} (a :: k) (b :: k). Compare a b ~ 'GT => OrderingI a b
Instances
Instances details
Show (OrderingI a b) Source
Instance details

Defined in GHC.Internal.Data.Type.Ord

Methods

showsPrec :: Int -> OrderingI a b -> ShowS Source

show :: OrderingI a b -> String Source

showList :: [OrderingI a b] -> ShowS Source

Eq (OrderingI a b) Source
Instance details

Defined in GHC.Internal.Data.Type.Ord

Methods

(==) :: OrderingI a b -> OrderingI a b -> Bool Source

(/=) :: OrderingI a b -> OrderingI a b -> Bool Source

type (<=) (x :: t) (y :: t) = Assert (x <=? y) (LeErrMsg x y :: Constraint) infix 4 Source

Comparison (<=) of comparable types, as a constraint.

Since: base-4.16.0.0

type (<=?) (m :: k) (n :: k) = OrdCond (Compare m n) 'True 'True 'False infix 4 Source

Comparison (<=) of comparable types, as a function.

Since: base-4.16.0.0

type (>=) (x :: t) (y :: t) = Assert (x >=? y) (GeErrMsg x y :: Constraint) infix 4 Source

Comparison (>=) of comparable types, as a constraint.

Since: base-4.16.0.0

type (>=?) (m :: k) (n :: k) = OrdCond (Compare m n) 'False 'True 'True infix 4 Source

Comparison (>=) of comparable types, as a function.

Since: base-4.16.0.0

type (>) (x :: t) (y :: t) = Assert (x >? y) (GtErrMsg x y :: Constraint) infix 4 Source

Comparison (>) of comparable types, as a constraint.

Since: base-4.16.0.0

type (>?) (m :: k) (n :: k) = OrdCond (Compare m n) 'False 'False 'True infix 4 Source

Comparison (>) of comparable types, as a function.

Since: base-4.16.0.0

type (<) (x :: t) (y :: t) = Assert (x <? y) (LtErrMsg x y :: Constraint) infix 4 Source

Comparison (<) of comparable types, as a constraint.

Since: base-4.16.0.0

type (<?) (m :: k) (n :: k) = OrdCond (Compare m n) 'True 'False 'False infix 4 Source

Comparison (<) of comparable types, as a function.

Since: base-4.16.0.0

type Max (m :: k) (n :: k) = OrdCond (Compare m n) n n m Source

Maximum between two comparable types.

Since: base-4.16.0.0

type Min (m :: k) (n :: k) = OrdCond (Compare m n) m m n Source

Minimum between two comparable types.

Since: base-4.16.0.0

type family OrdCond (o :: Ordering) (lt :: k) (eq :: k) (gt :: k) :: k where ... Source

A case statement on Ordering.

OrdCond c l e g is l when c ~ LT, e when c ~ EQ, and g when c ~ GT.

Since: base-4.16.0.0

Equations

OrdCond 'LT (lt :: k) (eq :: k) (gt :: k) = lt
OrdCond 'EQ (lt :: k) (eq :: k) (gt :: k) = eq
OrdCond 'GT (lt :: k) (eq :: k) (gt :: k) = gt

© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/9.12.1/docs/libraries/base-4.21.0.0-8e62/Data-Type-Ord.html