Copyright	(C) 2008-2013 Edward Kmett
License	BSD-style (see LICENSE)
Maintainer	Richard Eisenberg (eir@cis.upenn.edu)
Stability	experimental
Portability	non-portable
Safe Haskell	Trustworthy
Language	Haskell2010

Data.Singletons.Void

Description

This module is a reimplementation of Edward Kmett's void package. It is included within singletons to avoid depending on void and all the packages that depends on (including text). If this causes problems for you (that singletons has its own Void type), please let me (Richard Eisenberg) know at eir at cis.upenn.edu.

Synopsis

Documentation

data Void Source

A logically uninhabited data type.

Instances

Eq Void
Data Void
Ord Void
Read Void	Reading a `Void` value is always a parse error, considering `Void` as a data type with no constructors.
Show Void
Ix Void
Generic Void
Exception Void
Typeable * Void
type Rep Void

absurd :: Void -> a Source

Since Void values logically don't exist, this witnesses the logical reasoning tool of "ex falso quodlibet".

vacuous :: Functor f => f Void -> f a Source

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

vacuousM :: Monad m => m Void -> m a Source

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