WeakMap.prototype.set()

The set() method adds a new element with a specified key and value to a WeakMap object.

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Syntax

wm.set(key, value);

Parameters

key

Required. Must be object. The key of the element to add to the WeakMap object.

value

Required. Any value. The value of the element to add to the WeakMap object.

Return value

The WeakMap object.

Examples

Using the set method

var wm = new WeakMap();
var obj = {};

// Add new elements to the WeakMap
wm.set(obj, 'foo').set(window, 'bar'); // chainable

// Update an element in the WeakMap
wm.set(obj, 'baz');

Specifications

Browser compatibility

See also

• WeakMap
• WeakMap.prototype.get()
• WeakMap.prototype.has()