kotlin-stdlib/com.javiersc.kotlin.stdlib/Either/isRight

isRight

Returns true if this is a Right, false otherwise.

inline fun isRight(predicate: (B) -> Boolean): Boolean

Returns false if Left or returns the result of the given predicate to the Right value.

import arrow.core.Either
import arrow.core.Either.Left
import arrow.core.Either.Right
import io.kotest.matchers.shouldBe

fun test() {
 Right(12).isRight { it 10 } shouldBe true
 Right(7).isRight { it 10 } shouldBe false

 val left: Either<String, Int> = Left("Hello World")
 left.isRight { it 10 } shouldBe false
}