Safe Haskell	None
Language	Haskell2010

Darcs.UI.Options.Iso

Contents

Isomorphisms

Synopsis

data Iso a b = Iso (a -> b) (b -> a)
class IsoFunctor f where
- imap :: Iso a b -> f a -> f b
under :: Functor f => Iso a b -> Iso (f a) (f b)
cps :: Iso a b -> Iso (a -> c) (b -> c)

Isomorphisms

data Iso a b Source #

Lightweight type ismomorphisms (a.k.a. invertible functions). If

Iso fw bw :: Iso a b

then fw and bw are supposed to satisfy

fw . bw = id = bw . fw

Constructors

Iso (a -> b) (b -> a)

class IsoFunctor f where Source #

Lift an isomorphism between a and b to one between f a and f b. Like Functor, except we can only map invertible functions (i.e. an Isomorphisms).

Methods

imap :: Iso a b -> f a -> f b Source #

Instances

IsoFunctor (RawOptSpec f) Source #
Instance details Defined in Darcs.UI.Options.Util Methods imap :: Iso a b -> RawOptSpec f a -> RawOptSpec f b Source #
IsoFunctor (OptSpec d f a) Source #
Instance details Defined in Darcs.UI.Options.Core Methods imap :: Iso a0 b -> OptSpec d f a a0 -> OptSpec d f a b Source #

under :: Functor f => Iso a b -> Iso (f a) (f b) Source #

Apply an iso under a functor.

cps :: Iso a b -> Iso (a -> c) (b -> c) Source #

Apply an iso under cps (which is a cofunctor).