Bound.Var

Documentation

data Var b a

"I am not a number, I am a free monad!"

A Var b a is a variable that may either be "bound" (B) or "free" (F).

(It is also technically a free monad in the same near-trivial sense as Either.)

Constructors

B b

this is a bound variable

F a

this is a free variable

Instances

Bifunctor Var

Bitraversable Var

Bifoldable Var

Serial2 Var

Hashable2 Var

Eq2 Var

Ord2 Var

Show2 Var

Read2 Var

Monad (Var b)

Functor (Var b)

Applicative (Var b)

Foldable (Var b)

Traversable (Var b)

Serial b => Serial1 (Var b)

Hashable b => Hashable1 (Var b)

Eq b => Eq1 (Var b)

Ord b => Ord1 (Var b)

Show b => Show1 (Var b)

Read b => Read1 (Var b)

(Eq b, Eq a) => Eq (Var b a)

(Data b, Data a) => Data (Var b a)

(Ord b, Ord a) => Ord (Var b a)

(Read b, Read a) => Read (Var b a)

(Show b, Show a) => Show (Var b a)

Generic (Var b a)

(Binary b, Binary a) => Binary (Var b a)

(Serial b, Serial a) => Serial (Var b a)

(Serialize b, Serialize a) => Serialize (Var b a)

(Hashable b, Hashable a) => Hashable (Var b a)

type Rep (Var b a)

unvar :: (b -> r) -> (a -> r) -> Var b a -> r

_B :: (Choice p, Applicative f) => p b (f b') -> p (Var b a) (f (Var b' a))

This provides a Prism that can be used with lens library to access a bound Var.

_B :: Prism (Var b a) (Var b' a) b b'@

_F :: (Choice p, Applicative f) => p a (f a') -> p (Var b a) (f (Var b a'))

This provides a Prism that can be used with lens library to access a free Var.

_F :: Prism (Var b a) (Var b a') a a'@