Copyright	(C) 2012 Edward Kmett
License	BSD-style (see the file LICENSE)
Maintainer	Edward Kmett <ekmett@gmail.com>
Stability	experimental
Portability	portable
Safe Haskell	Trustworthy
Language	Haskell98

Bound.Var

Description

Synopsis

Documentation

data Var b a Source

"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

Bitraversable Var
Bifunctor 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)
Typeable (* -> * -> *) Var
type Rep (Var b a)

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

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

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')) Source

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'@