Is there an equivalent of Nil for Set in scala?
I tried using Nil as a value for Set, but I got an error (expected since the type of Nil is List)
Thanks
Is there an equivalent of Nil for Set in scala? I tried using Nil
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Is there an equivalent of Nil for Set in scala?
I tried using Nil as a value for Set, but I got an error (expected since the type of Nil is List)
Thanks
Set.emptyis that set; although you can’t get at it directly, it turns out that it is just a private object in theSetcompanion object (called, obviously enough,EmptySet). All thatSet.emptydoes is return that set with a cast to the correct type.It is done this way, instead of with
Nil, because sets are invariant in their parameters.NilisList[Nothing](), but you couldn’t add anything to aSet[Nothing]().If you need to specify the type of your empty set, you can use e.g.
Set.empty[String].