is-weakset

What is is-weakset?

The is-weakset npm package is a utility that allows developers to check if a given value is an instance of a WeakSet. WeakSets are collections of objects, similar to Sets, but with some key differences. Specifically, the objects in a WeakSet are held weakly, meaning if there is no other reference to an object stored in the WeakSet, it can be garbage collected. This package provides a simple and straightforward way to determine if a value is a WeakSet, which can be particularly useful when working with complex data structures or when implementing certain types of data handling logic.

What are is-weakset's main functionalities?

Check if a value is a WeakSet

This feature allows developers to check if a given value is an instance of a WeakSet. The code sample demonstrates how to use the is-weakset package to verify if a variable (ws) is a WeakSet, which returns true. It also shows that using the same function with a Set (notWs) returns false, illustrating the package's ability to distinguish between WeakSets and other types of objects.

"use strict";\nconst isWeakset = require('is-weakset');\n\nconst ws = new WeakSet();\nconst result = isWeakset(ws); // true\n\nconsole.log(result); // Outputs: true\n\nconst notWs = new Set();\nconsole.log(isWeakset(notWs)); // Outputs: false

Other packages similar to is-weakset

is

The 'is' package is a comprehensive type-checking library that offers a wide range of functions to determine the types of variables, including checks for built-in JavaScript types and more complex structures. While it provides a broader scope of functionality compared to is-weakset, it includes the ability to check for WeakSet instances among its many type-checking capabilities, making it a more versatile option for developers who need to perform various types of type checks.

lodash.isweakset

lodash.isweakset is a method from the Lodash library, a popular utility library that provides a lot of methods for working with arrays, numbers, objects, strings, etc. Specifically, lodash.isweakset is focused on checking if a value is a WeakSet, similar to is-weakset. However, being part of the Lodash library, it benefits from integration with Lodash's other utilities, offering a more comprehensive toolkit for developers who are already using Lodash in their projects.

README

is-weakset

Is this value a JS WeakSet? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Example

var isWeakSet = require('is-weakset');
assert(!isWeakSet(function () {}));
assert(!isWeakSet(null));
assert(!isWeakSet(function* () { yield 42; return Infinity; });
assert(!isWeakSet(Symbol('foo')));
assert(!isWeakSet(1n));
assert(!isWeakSet(Object(1n)));

assert(!isWeakSet(new Set()));
assert(!isWeakSet(new WeakMap()));
assert(!isWeakSet(new Map()));

assert(isWeakSet(new WeakSet()));

class MyWeakSet extends WeakSet {}
assert(isWeakSet(new MyWeakSet()));

Tests

Simply clone the repo, npm install, and run npm test