Benchmark: Includes (array) vs Has (Map)

Script Preparation code:

var a = [1,2,3,4,5,6,7,8,9,10]
var b = new Map([[1,1],[2,1],[3,1],[4,1],[5,1],[6,1],[7,1],[8,1],[9,1],[10,1]])

Tests:

Includes (array)
a.includes(10)
Has (Map)
b.has(10)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Includes (array)
Has (Map)

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.63 Safari/537.36 Edg/102.0.1245.33

Browser/OS: Chrome 102 on Windows

View result in a separate tab

Test name	Executions per second
Includes (array)	11001350.0 Ops/sec
Has (Map)	10671202.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided benchmark.

The test is comparing two approaches for checking if an element exists in a collection: using `includes()` on an array versus using `has()` on a Map.

**Includes() approach**

This approach uses the `includes()` method to check if the value 10 is present in the array `a`. The `includes()` method iterates over the elements of the array and returns a boolean indicating whether the specified element exists.

Pros:

* Widely supported across modern browsers
* Simple and straightforward to use

Cons:

* Can be slower than other approaches for very large arrays, as it requires iterating over all elements.
* May not be suitable for cases where performance is critical.

**Has() approach**

This approach uses the `has()` method on a Map to check if the key 10 exists. The `has()` method checks if a specific key or property exists in the Map and returns a boolean indicating whether it does.

Pros:

* Can be faster than the `includes()` approach for very large collections, as it only requires checking one entry.
* Suitable for cases where performance is critical.

Cons:

* Not all browsers support Maps (e.g., older versions of Internet Explorer).
* May require additional setup or configuration to work with certain types of data.

Now, let's take a closer look at the libraries and special features being used in this benchmark:

* **Map**: A Map is an object that stores key-value pairs. In this benchmark, we're using a Map `b` to store integer keys mapped to their corresponding values.
* No special JavaScript features or syntax are being tested in this benchmark.

Other alternatives for this type of test could include:

* Using a Set instead of a Map: Sets provide fast membership testing and would be suitable for similar performance-critical cases. However, they may not work with older browsers that don't support Sets.
* Using a binary search algorithm to find the element in the array or Map: This approach can be faster than linear searches but requires more complex implementation.

In general, when choosing between these approaches, consider factors such as:

* Performance requirements
* Browser support and compatibility
* Complexity of implementation

For most cases, using `includes()` on an array will provide a simple and widely supported solution. However, for performance-critical applications or specific use cases where Maps are necessary, the `has()` approach may be preferable.

Related benchmarks:

Includes (array) vs Has (Map) (version: 0)

Comparing performance of: Includes (array) vs Has (Map)

Created: 2 years ago by: Registered User

Jump to the latest result

Includes (array)

Has (Map)

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):