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kotlinlang

Not sure if this belongs here, but why are the implementations of `toSet` and `toMutableSet` different? Can't they both use `LinkedHashSet(this)` (which seems to be more performant)?

From what I can tell, `toMutableSet()` uses a custom `mapCapacity` method to make the set's underlying hash space slightly larger than necessary to accommodate new entries, while `toSet()` is content with the JVM default as there will be no more new entries.

<https://github.com/JetBrains/kotlin/blob/05896a42da04620a2e8ca35e952ff31c3c48aa9d/libraries/stdlib/common/src/generated/_Collections.kt#L1343|Iterable.toSet> • <https://github.com/JetBrains/kotlin/blob/05896a42da04620a2e8ca35e952ff31c3c48aa9d/libraries/stdlib/common/src/generated/_Collections.kt#L1694|Iterable.toMutableSet>

`toSet` has specific cases for the empty set and the singleton set (both use less memory than real sets).