Last updated on Jan 01 2023

Monkey Patching

JavaScript Monkey patching is a technique used to extend or modify the behavior of existing functions in JavaScript. This can be useful in a variety of situations, such as when a third-party library does not provide the functionality you need, or when you want to add additional features to an existing function.

To monkey patch a function, you simply overwrite it with a new implementation. This is typically done using the following syntax:

originalFunction = originalFunction.bind(this);

This code saves a reference to the original function, then overwrites it with a new function that has the same name and arguments as the original. This new function can then call the original function using the saved reference, and can also add additional functionality before or after the original function is called.

One common use for monkey patching is to add additional functionality to a third-party library. For example, if you are using a library that does not provide a particular feature, you can monkey patch one of its functions to add the desired functionality.

Another use for monkey patching is to fix bugs in existing code. If you find a bug in a library or application, you can monkey patch the affected function to fix the bug without modifying the original code. This can be especially useful when you do not have access to the source code, or when you want to avoid the hassle of having to update and maintain multiple versions of the code.

It's important to note that monkey patching should be used with caution. Overwriting existing functions can lead to unpredictable behavior, and can cause conflicts with other code that relies on the original function. In addition, monkey patching can make it difficult to debug and maintain your code, as it can be difficult to keep track of all the different patches that have been applied.

To avoid these problems, it's best to use monkey patching sparingly and only when necessary. If you do use monkey patching, it's a good idea to document your changes and test your code thoroughly.