Which JavaScript method is used to remove the last element from an array and return that element?

Understanding the JavaScript pop() Method

The correct answer to the question, "Which JavaScript method is used to remove the last element from an array and return that element?" is the pop() method. This method is a widely-utilized JavaScript function utilized to manipulate arrays.

How does the pop() Method Work?

The pop() method in JavaScript is used to remove the last item from an array and return that item. This method modifies the original array on which it's called, by reducing its length by one. Unlike some other methods, pop() specifically targets and operates on the final element of an array.

Here's an example on how to use this method:

const fruits = ["apple", "banana", "mango"];
const lastFruit = fruits.pop();
console.log(lastFruit);  // Outputs: mango
console.log(fruits);  // Outputs: ["apple", "banana"]

In the above example, after calling the pop() method on the fruits array, the value "mango" is removed from the array and stored in the lastFruit variable.

Best Practices and Additional Insights

While pop() can be a handy way to manipulate arrays in JavaScript, it's important to note some best practices and insights:

  • Since pop() directly modifies the original array, it's recommended to use this method carefully especially when preserving the original state of the array is critical in your code.
  • Should you call pop() on an empty array, it will return undefined, and the original array remains empty, given there are no items to remove. Therefore, it's best to check if an array is not empty before using pop().
  • Unlike pop(), other JavaScript array methods such as push() add elements to an array, whereas last() and removeLast() do not exist in native JavaScript.

Understanding how and when to use pop(), along with other array methods in JavaScript, is essential in handling and manipulating data structures efficiently. This can help in writing cleaner, more readable code, and also in succeeding in technical interviews or quizzes where such knowledge is tested.

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