Collection

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Set API ​

Set<E> extends Collection<E> for ordered collections of unique elements. Duplicate values are silently ignored on insertion. Sets do not support indexed access. See Collection API for inherited methods.

Conversion ​

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toMutable(): MutableSet<E>

Always creates a new mutable copy.

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toImmutable(): ImmutableSet<E>

Returns an immutable set. May return itself if already immutable.

MutableSet Methods ​

MutableSet does not add methods beyond those inherited from MutableCollection. See Collection API for add(), addFirst(), removeElement(), removeFirst(), removeLast(), and other mutation methods.

addFirst on Sets

addFirst() uses move-to-front semantics on sets: if the element already exists, it is moved to the first position. If the element is already first, the call is a no-op. See the Set guide for examples.

ImmutableSet Methods ​

ImmutableSet does not add methods beyond those inherited from ImmutableCollection. See Collection API for add(), addFirst(), removeElement(), removeFirst(), removeLast(), and other mutation methods.