How to Fix “undefined is not a function” in JavaScript

KASATA
2 min readApr 25, 2024

One of the common errors encountered in JavaScript is the “undefined is not a function” error. This JavaScript runtime error is thrown when you try to call a variable or property as if it were a function, but it’s actually undefined or not a function at all. In this article, we’ll go through some troubleshooting techniques that could help you resolve this error.

Understanding the Error

Before we dive into the debugging and resolution techniques, let’s take a moment to understand what this error…

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KASATA

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