WeakSet() constructor
The WeakSet()
constructor creates WeakSet
objects.
Syntax
Parameters
iterable
Optional-
If an iterable object is passed, all of its elements will be added to the new
WeakSet
. null is treated as undefined.
Examples
Using the WeakSet object
js
const ws = new WeakSet();
const foo = {};
const bar = {};
ws.add(foo);
ws.add(bar);
ws.has(foo); // true
ws.has(bar); // true
ws.delete(foo); // removes foo from the set
ws.has(foo); // false, foo has been removed
ws.has(bar); // true, bar is retained
Note that foo !== bar
. While they are similar objects, they are not
the same object. And so they are both added to the set.
Specifications
Specification |
---|
ECMAScript Language Specification # sec-weakset-constructor |
Browser compatibility
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