February 2018
Intermediate to advanced
298 pages
8h 22m
English
Content preview from Learn ECMAScript - Second Edition
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WeakSet
Here are the differences between Set and WeakSet objects:
- A Set can store primitive types and object references whereas a WeakSet object can only store object references
- One important features WeakSet objects is that if there is no other reference to an object stored in a WeakSet object then they are garbage-collected
- Lastly, a WeakSet object is not enumerable: that is, you cannot find its size; it also doesn't implement the iterable protocol
Apart from these three differences, WeakSet behaves exactly the same way as Set. Everything else apart from these three differences is same between a Set and WeakSet object.
A WeakSet object is created using the WeakSet constructor. You cannot pass an iterable object as an argument to a WeakSet ...
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