Benchmark: array indexOf vs includes vs some using numbers

Script Preparation code:

var array = [1, 2, 3,4,5,6,7,8,9,10]

Tests:

IndexOf
array.indexOf(7)
Includes
array.includes(7)
some
array.some(v => v === 7)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
IndexOf
Includes
some

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 2 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the explanation of the provided benchmark.

**Benchmark Overview**

The benchmark is designed to compare the performance of three different methods for finding if an array contains a specific value:

1. `array.indexOf(value)`
2. `array.includes(value)`
3. `array.some(v => v === value)`

These methods are commonly used in JavaScript, and their performance can vary depending on the browser and platform.

**Options Compared**

The three options being compared are:

* `indexOf`: Returns the index of the first occurrence of the specified value. If the value is not found, it returns -1.
* `includes`: Returns a boolean indicating whether the array includes the specified value.
* `some`: Returns a boolean indicating whether at least one element in the array satisfies the provided condition.

**Pros and Cons**

Here's a brief overview of each method:

* `indexOf`:
	+ Pros: Can be faster for exact matches, as it returns an index value immediately.
	+ Cons: May incur additional overhead if the array is large or the value is not found, leading to unnecessary computations.
* `includes`:
	+ Pros: Generally faster than `indexOf`, especially for larger arrays, since it doesn't require computing an index value.
	+ Cons: May have slightly lower performance due to the need to iterate through the array.
* `some`:
	+ Pros: Can be more flexible, as it allows testing multiple conditions and can short-circuit early if the condition is not met.
	+ Cons: Typically slower than `indexOf` and `includes`, especially for large arrays, since it requires iterating through the elements.

**Library and Special JS Features**

None of these methods rely on any external libraries or special JavaScript features. They are built-in array methods that are part of the ECMAScript specification.

**Other Considerations**

When choosing between these methods, consider the specific requirements of your use case:

* If you need to find the index of a value for further processing, `indexOf` might be a better choice.
* If you only care about whether the value is present in the array, `includes` could be sufficient.
* If you need to test multiple conditions or want more control over the iteration process, `some` might be the way to go.

**Alternative Approaches**

Other alternatives for finding values in an array include:

* Using a custom function with a loop: e.g., `function findValue(array, value) { for (let i = 0; i < array.length; i++) { if (array[i] === value) return true; } return false; }`
* Using `Array.prototype.every()` and negating the result: e.g., `return !array.some(v => v !== value)`
* Using a dedicated library or function for fast array lookups, such as `fast-integer-indexed-array` or `binary-search`.

Keep in mind that these alternatives may have different performance characteristics and trade-offs compared to the built-in methods.

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:103.0) Gecko/20100101 Firefox/103.0

Browser/OS: Firefox 103 on Windows

View result in a separate tab

Test name	Executions per second
IndexOf	54651660.0 Ops/sec
Includes	54289260.0 Ops/sec
some	93194040.0 Ops/sec

Related benchmarks:

array indexOf vs includes vs some using numbers (version: 0)

performance comparison of ways to find if an array contains a value

Comparing performance of: IndexOf vs Includes vs some

Created: 2 years ago by: Guest

Jump to the latest result

IndexOf

Includes

some

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 2 days ago):