cajeta.collection.ImmutableSet — immutable, hash-indexed set: a frozen, de-duplicated snapshot of an ArrayList<T>. Members are stored once in a dense array (so the set is cheaply indexable and streamable in first-seen order) with a separate open-addressing table for O(1) contains, built once at construction — no removal, tombstones, or resize. Hashing and equality follow the HashMap / HashSet contract: T.hash() selects the bucket, == decides membership.

ArrayList<int32> src = heap ArrayList<int32>();
src.add(1);
src.add(2);
src.add(2);

// The `#` surrenders `src`, whose members move into the set.
ImmutableSet<int32> set = heap ImmutableSet<int32>(#src);
int64 n = set.count();          // 2 — duplicate dropped
boolean has = set.contains(2);  // true
int32 first = set.get(0);       // 1 — first-seen order preserved

Methods

Signature
`ImmutableSet(#ArrayList<T> src)` ⚑	Build a frozen, de-duplicated set from `src` (first occurrence wins), which is consumed, so the call must write `#src`
`int64 count()`	Number of unique members
`boolean isEmpty()`	`count() == 0`
`boolean contains(T v)`	True iff `v` is a member; O(1) average
`T get(int32 i)`	Member at dense index `i` (0-based, first-seen order), or the type’s zero value if out of range
`#ArrayStream<T> stream()`	Heap-allocated `ArrayStream` over the unique members, first-seen order

⚑ = @EntryPoint

ImmutableSet<T>

Methods

See also