jchucomponents-core/com.jeluchu.jchucomponents.core.functional/Either/Left

Left

data class Left<out L>(val a: L) : Either<L, Nothing>

Represents the left side of Either class which by convention is a "Failure".

Constructors

Left

constructor(a: L)

Properties

val a: L

isLeft

val isLeft: Boolean

Returns true if this is a Left, false otherwise.

isRight

val isRight: Boolean

Returns true if this is a Right, false otherwise.

Functions

flatMap

fun <T, L, R> Either<L, R>.flatMap(fn: (R) -> Either<L, T>): Either<L, T>

Right-biased flatMap() FP convention which means that Right is assumed to be the default case to operate on. If it is Left, operations like map, flatMap, ... return the Left value unchanged.

fold

fun fold(fnL: (L) -> Any, fnR: (Nothing) -> Any): Any

Applies fnL if this is a Left or fnR if this is a Right.

getOrElse

fun <L, R> Either<L, R>.getOrElse(value: R): R

Returns the value from this Right or the given argument if this is a Left. Right(12).getOrElse(17) RETURNS 12 and Left(12).getOrElse(17) RETURNS 17

left

fun <L> left(a: L): Either.Left<L>

Creates a Left type.

map

fun <T, L, R> Either<L, R>.map(fn: (R) -> T): Either<L, T>

Right-biased map() FP convention which means that Right is assumed to be the default case to operate on. If it is Left, operations like map, flatMap, ... return the Left value unchanged.

right

fun <R> right(b: R): Either.Right<R>

Creates a Left type.