WeakMap.prototype.set()
The set()
method adds a new element with a specified key
and value to a WeakMap
object.
Try it
Syntax
js
set(key, value)
Parameters
key
-
Must be either an object or a non-registered symbol. The key of the entry to add to the
WeakMap
object. value
-
Any value representing the value of the entry to add to the
WeakMap
object.
Return value
The WeakMap
object.
Exceptions
TypeError
-
Thrown if
key
is not an object or a non-registered symbol.
Examples
Using the set() method
js
const wm = new WeakMap();
const 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");
// Using a non-registered symbol as key
const sym = Symbol("foo");
wm.set(sym, "baz");
wm.set(Symbol.iterator, "qux");
Specifications
Specification |
---|
ECMAScript Language Specification # sec-weakmap.prototype.set |
Browser compatibility
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