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kotlinlang

Wouldn’t it be nice if `.toList()`, `.map()`, `.filter()`, `listOf()`, etc. use some immutable `List` subclass internally, so that subsequent calls to `.toList()` don’t have to create another copy? :slightly_smiling_face:

Would be great for defensive copy patterns, since you don’t know whether the list you get is immutable or not.

No it isn’t. Where does it say that?

Documentation only states “Returns a List containing all elements.“:
<https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/to-list.html>

hmm, but we have `.asXxx()` for returning view on `this` collection

`.asXX()` could be immutable depending on whether the underlying collection is immutable, hence `.toList()` could even here just return `this` in some cases :smile: