What is the method for determining the size of a WeakMap?

I am working with a WeakMap that looks like the following:

let newObj = new WeakMap();
let key1={"a":1};
let key2={"b":2};
let key3={"c":3};

newObj.set(key1,"value1");
newObj.set(key2,"value2");
newObj.set(key3,"value3");

Is there a method to determine the number of keys stored in newObj?

I attempted using Object.keys(newObj).length, but it seems to be returning 0.

Answer №1

According to information from the official documentation

Due to the inability of a WeakMap to track the liveliness of its keys, the keys cannot be enumerated. There is no functionality that allows for retrieving a list of keys.

This implies that determining the number of keys within a WeakMap is also not feasible.

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