errorIfEmpty

inline fun <T, R : Iterable<T>> ApiResult<R>.errorIfEmpty(exception: () -> Exception = { ConditionNotSatisfiedException("Collection was empty") }): ApiResult<R>

@JvmName(name = "sequenceErrorIfEmpty")

inline fun <T, R : Sequence<T>> ApiResult<R>.errorIfEmpty(exception: () -> Exception = { ConditionNotSatisfiedException("Sequence was empty") }): ApiResult<R>

Makes this an error if the collection is empty.