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/Haskell 8

Data.Type.Bool

License BSD-style (see the LICENSE file in the distribution)
Maintainer libraries@haskell.org
Stability experimental
Portability not portable
Safe Haskell Safe
Language Haskell2010

Description

Basic operations on type-level Booleans.

Since: 4.7.0.0

type family If cond tru fls where ... Source

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

Equations

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

type family a && b where ... infixr 3 Source

Type-level "and"

Equations

False && a = False
True && a = a
a && False = False
a && True = a
a && a = a

type family a || b where ... infixr 2 Source

Type-level "or"

Equations

False || a = a
True || a = True
a || False = a
a || True = True
a || a = a

type family Not a where ... Source

Type-level "not"

Equations

Not False = True
Not True = False

© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/8.0.1/docs/html/libraries/base-4.9.0.0/Data-Type-Bool.html