Data.Star

Documentation

class Semiring a => Star a where

A Star semiring adds one operation, star to a Semiring, such that it follows the law:

star x = one + x * star x = one + star x * x

Another operation, aplus, can be defined in terms of star:

aplus x = x * star x

Minimal complete definition

star | aplus

Methods

star :: a -> a

aplus :: a -> a

Instances

Star Bool

Methods

star :: Bool -> Bool

aplus :: Bool -> Bool

Star ()

Methods

star :: () -> ()

aplus :: () -> ()

(Eq a, Monoid a) => Star (Endo a)

Methods

star :: Endo a -> Endo a

aplus :: Endo a -> Endo a

Star b => Star (a -> b)

Methods

star :: (a -> b) -> a -> b

aplus :: (a -> b) -> a -> b