base-4.11.1.0: Basic libraries

LicenseBSD-style (see the LICENSE file in the distribution)
Maintainer[email protected]
Stabilityexperimental
Portabilitynot portable
Safe HaskellSafe
LanguageHaskell2010

Data.Type.Bool

Description

Basic operations on type-level Booleans.

Since: base-4.7.0.0

Synopsis
  • type family If cond tru fls where ...
  • type family a && b where ...
  • type family a || b where ...
  • type family Not a = res | res -> a where ...

Documentation

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 = res | res -> a where ... Source #

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

Since: base-4.7.0.0

Equations

Not False = True 
Not True = False