Benchmark: Array.includes vs Set.has vas Map.has 2

Script Preparation code:

var a = new Array(1000).fill(null).map((_, index) => index);
var b = new Set(Array.from(a));

Tests:

Array includes
return a.includes(9);
Set has
return b.has(9);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array includes
Set has

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Definition**

The benchmark is designed to compare the performance of three different data structures in JavaScript: `Array.includes`, `Set.has`, and `Map.has`. The script preparation code creates two arrays (`a` and `b`) with 1000 elements each. One array is converted to a set, which is then used to create another variable `b`.

**Options Compared**

The three options being compared are:

1. **Array.includes**: A method that checks if an element exists in the array.
2. **Set.has**: A method that checks if an element exists in the set.
3. **Map.has**: A method that checks if a key exists in the map.

**Pros and Cons of Each Approach**

Here's a brief overview of each approach:

1. **Array.includes**
	* Pros: Widely supported, easy to use, and fast for large arrays.
	* Cons: May have performance issues for very large arrays due to its iterative nature.
2. **Set.has**
	* Pros: Fast lookup times, especially when dealing with unique values or sets of unique values. Sets are also more memory-efficient than arrays.
	* Cons: Not designed for sequential access or random element selection. Requires converting an array to a set before using this method.
3. **Map.has**
	* Pros: Similar performance characteristics to `Set.has`, but with the added benefit of key-value pairs and efficient lookup times.
	* Cons: Requires creating a map object, which may have overhead compared to arrays or sets.

**Library Usage**

In this benchmark, no specific libraries are used beyond what's built into JavaScript. However, it's worth noting that some versions of Chrome (like Chrome 120) use the `Map.has` method under the hood due to its performance benefits for hash-based operations.

**Special JS Features/Syntax**

There doesn't appear to be any special or experimental JavaScript features/syntax used in this benchmark. The focus is on comparing three well-established methods.

**Alternative Approaches**

If you were to create an alternative benchmark, you could consider adding other data structures or algorithms, such as:

* **Array.includes alternatives**: Implementing a more efficient algorithm for finding elements in large arrays, like using `bitwise operations`.
* **Set and Map optimizations**: Investigating ways to optimize set and map lookups further, such as using caching or pre-computation of hash values.
* **Multi-threaded testing**: Using multiple threads or processes to test the performance of each method across different CPU architectures.

Keep in mind that benchmarks like MeasureThat.net often focus on a specific problem domain (in this case, lookup operations) and may not cover all possible scenarios.

Latest run results:

Run details: (Test run date: 15 days ago)

User agent: Mozilla/5.0 (Android 14; Mobile; rv:132.0) Gecko/132.0 Firefox/132.0

Browser/OS: Firefox Mobile 132 on Android

View result in a separate tab

Test name	Executions per second
Array includes	8877871.0 Ops/sec
Set has	863853312.0 Ops/sec

Related benchmarks:

Array.includes vs Set.has vas Map.has 2 (version: 0)

Comparing performance of: Array includes vs Set has

Created: 10 months ago by: Guest

Jump to the latest result

Array includes

Set has

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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