es6 Map and Set complexity, v8 implementation

javascript ecmascript-6 v8
Uri picture Uri · Nov 9, 2015 · Viewed 17.9k times · Source

Is it a fair assumption that in v8 implementation retrieval / lookup is O(1)?

(I know that the standard doesn't guarantee that)

Answer

Bergi picture Bergi · Nov 9, 2015

Is it a fair assumption that in v8 implementation retrieval / lookup is O(1)?

Yes. V8 uses a variant of hash tables that generally have O(1) complexity for these operations.

For details, you might want to have a look at https://codereview.chromium.org/220293002/ where OrderedHashTable is implemented based on https://wiki.mozilla.org/User:Jorend/Deterministic_hash_tables.

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