``` object test { sealed class BizError { object Error1 : BizError() object Er...

# arrow

[raulraja]

object test {

    sealed class BizError  {
        object Error1 : BizError()
        object Error2 : BizError()
        object Error3: BizError()
    }

    val ops: List<ValidatedNel<BizError, Int>> = listOf(
            1.validNel(),
            1.validNel(),
            1.validNel(),
            BizError.Error1.invalidNel(),
            BizError.Error2.invalidNel(),
            BizError.Error3.invalidNel()
    )

    val result: ValidatedNel<BizError, Int> = ops.reduce { a, b ->
        a.combine(b, NonEmptyList.semigroup())
    }
}

[raulraja]

Similar but there is syntax for ValidatedNel to lift values into its context. @pguardiola repo has a good example. https://github.com/Guardiola31337/uiagesturegen/blob/master/uiagesturegen/src/main/kotlin/com/pguardiola/uigesturegen/dsl/interpreter.kt#L36

[raulraja]

You use combineK to automatically accumulate errors using the nonenptylist semigroup.

[raulraja]

Uiagesturegen is a free applicative DSL interpreted to Validated

[pguardiola]

There's also the "fail fast" approach, a different interpreter which interprets to Either