Let's break down the provided benchmark and explain what's being tested, compared, and their pros and cons.

Benchmark Definition

The benchmark is comparing two approaches to check if an element exists in an array:

1. arr.includes('3')
2. arr.indexOf('3') >= 0

Script Preparation Code

var arr = ['1', 2, '3'];

This code creates a sample array arr containing three elements.

Options Compared

The two options being compared are:

1. includes(): This method returns true if the specified element is found in the array, and false otherwise.
2. indexOf() >= 0: This approach checks if the index of the element in the array is greater than or equal to 0. If it is, the element exists in the array.

Pros and Cons

1. includes()
   • Pros:
     • More concise and readable code.
     • Often preferred by developers due to its simplicity and readability.
   • Cons:
     • Can be slower for large arrays since it iterates through the entire array to find a match.
2. indexOf() >= 0
   • Pros:
     • Can be faster than includes() for large arrays, as it stops iterating once it finds the first match or reaches the end of the array.
   • Cons:
     • Less readable and more verbose code.

Library Used

None in this benchmark. Both options are built-in JavaScript methods.

Special JS Feature/Syntax

None mentioned in this benchmark.

Other Alternatives

For checking if an element exists in an array, you can also use:

1. in: This operator returns a boolean value indicating whether the specified property (or key) is present in the object.
2. find(), findIndex(): These methods return the first element that matches the provided function or predicate.

Benchmark Preparation Code

The code preparation section provides the initial setup for the benchmark, creating a sample array arr and making it available to both test cases.

Individual Test Cases

Two test cases are defined:

1. includes
2. indexOf

These test cases measure the performance of each approach individually.

Latest Benchmark Result

The provided result shows the execution count per second for each test case, indicating how many times each operation was executed in a given time frame.

In summary, this benchmark compares two approaches to check if an element exists in an array: includes() and indexOf() >= 0. While both methods have their pros and cons, includes() is often preferred due to its simplicity but may be slower for large arrays. The benchmark provides valuable insights into the performance of these operations on various devices and browsers.