arrow-optics/arrow.optics.typeclasses/Snoc

Snoc

fun interface Snoc<S, A>

Snoc defines a Prism between a S and its init and last element A and thus can be seen as the reverse of Cons. It provides a way to attach or detach elements on the end side of a structure.

Parameters

source of Prism and init of Prism target.

last of Prism focus, A is supposed to be unique for a given S.

Types

Companion

object Companion

Properties

init

open val S.init: S?

Selects all elements except the last.

Functions

initOption

open fun initOption(): Optional<S, S>

Provides an Optional between S and its init S.

lastOption

open fun lastOption(): Optional<S, A>

Provides an Optional between S and its last element A.

snoc

abstract fun snoc(): Prism<S, Pair<S, A>>

Provides a Prism between a S and its init and last element A.

open infix fun S.snoc(last: A): S

Append an element A to S.

unsnoc

open fun S.unsnoc(): Pair<S, A>?

Deconstruct an S between its init and last element.