hi folks, I'm working on an `Either` instance for ...
# arrowp
prat
02/17/2018, 3:58 AMhi folks, I'm working on an
EitherHashjava.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Stringprat
02/17/2018, 4:01 AMthe instance looks pretty straightforward
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@instance(Either::class)
interface EitherHashInstance<L, R> : EitherEqInstance<L, R>, Hash<Either<L, R>> {
override fun EQL(): Eq<L>
override fun EQR(): Eq<R>
fun HSL(): Hash<L>
fun HSR(): Hash<R>
override fun hash(a: Either<L, R>): Int = when (a) {
is Either.Left -> HSL().hash(a.a).hashCode()
is Either.Right -> HSR().hash(a.b).hashCode()
}
}