void-0.7.2: A Haskell 98 logically uninhabited data type

Copyright(C) 2008-2015 Edward Kmett
LicenseBSD-style (see the file LICENSE)
MaintainerEdward Kmett <ekmett@gmail.com>
Stabilityprovisional
Portabilityportable
Safe HaskellUnsafe
LanguageHaskell98

Data.Void.Unsafe

Description

 

Synopsis

Documentation

unsafeVacuous :: Functor f => f Void -> f a #

If Void is uninhabited than any Functor that holds only values of the type Void is holding no values.

This is only safe for valid functors that do not perform GADT-like analysis on the argument.

unsafeVacuousM :: Monad m => m Void -> m a #

If Void is uninhabited then any Monad that holds values of type Void is holding no values.

This is only safe for valid monads that do not perform GADT-like analysis on the argument.