WeakSet

WeakSet

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Weak Set

[2] (2017-12-12 20:45:20 +09:00) <about:blank>

[3] WeakSet - JavaScript | MDN (2017-12-07 20:18:32 +09:00) <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet>

WeakSet