I have `method(input:Set<X>):Set<X>`, ...

# announcements

[geepawhill]

I have method(input:Set<X>):Set<X>, which wants to transform each element of the (small) set, seemingly a natural fit with .map { }, but, the transformation can produce invalid individual values, and if that occurs the method's result will be emptySet(). In other words, under some conditions i want to short-circuit the mapping and just return the empty set. I am wondering if there is some clever stream-ish/sequence-ish way to accomplish this, or should I just go with a for-in and a result accumulator?

[Zach Klippenstein (he/him) [MOD]]

map is inline, so you can return from the outer function inside its lambda.

[geepawhill]

So, something like .map { x = transform; if(x.isbad) return emptySet(); x } will work?

[Zach Klippenstein (he/him) [MOD]]

The easiest way to find out is to try it 😉 But yes, as long as your collection is not a Sequence (sequence operators are not inline).

[geepawhill]

I'll try it as soon as I get back to the 'puter. :)