Data.Algebra.Boolean.Negable

Documentation

data Neg a

Free Negable.

Constructors

Pos a

Positive value

Neg a

Negative value

Instances

Functor Neg

Typeable1 Neg

CoBoolean1 Neg

Eq a => Eq (Neg a)

Ord a => Ord (Neg a)

Read a => Read (Neg a)

Show a => Show (Neg a)

CoBoolean (Neg a)

Negable (Neg a)

class Negable x where

Class to represent invertible values.

Must obey the double negation law: not (not x) = x

The negation appears only in leafs of normal forms, and the underlying proposition class might have built-in negation, thus we use Negable.

Methods

not :: x -> x

Invert the value.

Instances

Negable Bool

Monoid m => Negable (Maybe m)

Negable (Neg a)

Negable (FreeBoolean a)

Negable a => Negable (NNF a)

(Ord a, Negable a) => Negable (DNF a)

(Ord a, Negable a) => Negable (CNF a)

(Ord a, Negable a) => Negable (NNF a)

Negable a => Negable (DNF a)

Negable a => Negable (CNF a)

(Negable a, Negable b) => Negable (Either a b)

(Negable a, Negable b) => Negable (a, b)