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I'm fairly new to scalaz and I've started out with validations. I have some validation functions of the form: def validateXyz(...): ValidationNEL[String, String] = ... I'm then using the applicative style to combine multiple validations and then call another function that also returns a validation: (validateXyz(...) |@| validateAbc(...)) { (first, second) => otherFunction(first, second) } where, def otherFunction(first: String, second: String): ValidationNEL[String, String] = ... However, when calling the above the resulting type is: val result: ValidationNEL[String, ValidationNEL[String, String]] = ... I can unpack this by calling fold on the result with two functions, the first which just propagates the NEL as a fail and the second which just propagates its argument: def propagateF(result: NonEmptyList[String]): ValidationNEL[String, String] = result.fail def propagateV(result: ValidationNEL[String, String]) = result result.fold(propagateF, propagateV) // result type: ValidationNEL[String, String] This works and returns the correct types and results. However it doesn't feel like the correct solution so I must be missing something. What do I need to do to avoid this horrible fold at the end?

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