Skip to content

HORIZON HASKELL Docs lts/ghc-10.0.x8fef28d2026-11-02Search packagesCtrl K

Theme: |

GHC 10.0.0.20260917 · lts/ghc-10.0.x · 8fef28d · 2026-11-02

Modulebase-4.23.0.0Haskell2010

Data.Type.Bool

Basic operations on type-level Booleans.

Synopsis

family If
family &&
family ||
family Not

Packagebase-4.23.0.0
Exports4
LanguageHaskell2010
LicenceBSD-3-Clause
SourceBool.hs

familytype family If (cond :: Bool) (tru :: k) (fls :: k) :: k where

Type-level If. If True a b ==> a; If False a b ==> b

Equations

If 'True tru fls = tru
If 'False tru fls = fls

familytype family (&&) (a :: Bool) (b :: Bool) :: Bool where

Type-level "and"

Equations

(&&) 'False a = 'False
(&&) 'True a = a
(&&) a 'False = 'False
(&&) a 'True = a
(&&) a a = a

familytype family (||) (a :: Bool) (b :: Bool) :: Bool where

Type-level "or"

Equations

(||) 'False a = a
(||) 'True a = 'True
(||) a 'False = a
(||) a 'True = 'True
(||) a a = a

familytype family Not (a :: Bool) :: Bool where

Type-level "not". An injective type family since 4.10.0.0.

Equations

Not 'False = 'True
Not 'True = 'False