do they not already?

# stdlib

[benleggiero]

do they not already?

[robin]

benleggiero: They don't. listOf() returns an ordinary ArrayList, for example. The immutability is only in the interface, because you're getting a List, but you can simply cast that to MutableList and do whatever you want.

[evanchooly]

well, the return type of listOf<T>() is List<T> which is “immutable”, iirc

[evanchooly]

but you can cast that to a MutableList

[benleggiero]

Yeah, after looking into the source code, the return type of listOf functions is the interface List, but unfortunately the implementation chosen is ArrayList, which is a MutableList