Package fj.data.optic

Optic data types adapted from the Scala Monocle library and inspired by the Haskell Lens library.

See: Description

Class Summary

Class	Description
Fold<S,A>	A Fold can be seen as a Getter with many targets or a weaker PTraversal which cannot modify its target.
Getter<S,A>	A Getter can be seen as a glorified get method between a type S and a type A.
Iso<S,A>	PIso when S = T and A = B
Lens<S,A>	PLens with a monomorphic set function
Optional<S,A>	POptional restricted to monomorphic update
PIso<S,T,A,B>	A PIso defines an isomorphism between types S, A and B, T: get reverse.get --------------------> --------------------> S A T B <-------------------- <-------------------- reverse.reverseGet reverseGet In addition, if f and g forms an isomorphism between `A` and `B`, i.e. if `f . g = id` and `g . f = id`, then a PIso defines an isomorphism between `S` and `T`: S T S T | | | | | | | | get | | reverseGet reverse.reverseGet | | reverse.get | | | | | f | | g | A --------> B A <-------- B A PIso is also a valid Getter, Fold, PLens, PPrism, POptional, PTraversal and PSetter
PLens<S,T,A,B>	A PLens can be seen as a pair of functions: - `get: S => A` i.e. from an `S`, we can extract an `A` - `set: (B, S) => T` i.e. if we replace an `A` by a `B` in an `S`, we obtain a `T` A PLens could also be defined as a weaker PIso where set requires an additional parameter than reverseGet.
POptional<S,T,A,B>	A POptional can be seen as a pair of functions: - `getOrModify: S => T \/ A` - `set : (B, S) => T` A POptional could also be defined as a weaker PLens and weaker PPrism POptional stands for Polymorphic Optional as it set and modify methods change a type `A` to `B` and `S` to `T`.
PPrism<S,T,A,B>	A PPrism can be seen as a pair of functions: - `getOrModify: S => T \/ A` - `reverseGet : B => T` A PPrism could also be defined as a weaker PIso where get can fail.
Prism<S,A>	PPrism restricted to monomorphic update
PSetter<S,T,A,B>	A PSetter is a generalisation of Functor map: - `map: (A => B) => F[A] => F[B]` - `modify: (A => B) => S => T` PSetter stands for Polymorphic Setter as it set and modify methods change a type `A` to `B` and `S` to `T`.
PTraversal<S,T,A,B>	A PTraversal can be seen as a POptional generalised to 0 to n targets where n can be infinite.
Setter<S,A>	PSetter with a monomorphic modify function
Traversal<S,A>

Package fj.data.optic Description

Optic data types adapted from the Scala Monocle library and inspired by the Haskell Lens library. See the Monocle Github page for an overview of the package.

See Also:

Monocle