Oh dear, Set.filter() returns a List rather than a...

# announcements

[mathew murphy]

Oh dear, Set.filter() returns a List rather than a Set.

[Casey Brooks]

It’s because .filter is defined on Iterable. There aren’t specific overrides for each Collection type

[karelpeeters]

You can do set.filterTo(mutableSetOf()) { ... }

[mathew murphy]

Thanks. Ideally I'd like a SortedSet and/or SortedMutableSet, but I think I can get away with containsAll on an unsorted Set because the sets are small.

[karelpeeters]

Well you can give it whatever collection type you want.

[mathew murphy]

Can I compare two sets for equality (independent of order of elements)?

[karelpeeters]

Yes, == does that.

[mathew murphy]

Too easy 🙂

[LS]

you can also use

set.asSequence().filter(predicate).toSet()
set.asSequence().filter(predicate).toMutableSet()
set.asSequence().filter(predicate).toSortedSet()