WeakMap.prototype.get() - JavaScript | MDN

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non-registered symbol

The value associated with the specified key in the WeakMap object. If the key can't be found, undefined is returned. Always returns undefined if key is not an object or a non-registered symbol.

WeakMap.prototype.delete()

WeakMap.prototype.set()

WeakMap.prototype.has()

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This page was last modified on Sep 22, 2025 by MDN contributors.

getOrInsertComputed()

[Symbol.hasInstance]()

__defineGetter__()

__defineSetter__()

__lookupGetter__()

__lookupSetter__()

propertyIsEnumerable()

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