# Introduction In this lab, we will be exploring how to check if all elements in an array are equal based on a provided mapping function using JavaScript. We will be using the `allEqualBy` function that applies the mapping function to the first element of the array and uses `Array.prototype.every()` to compare the rest of the elements to the first one. This lab is designed to help you understand the concept of mapping functions and how they can be used to compare elements in an array.
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