Benchmark: lodash flatmap vs array.flatMap fixed

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>

Script Preparation code:

var x = [1,2,3]
var y = [4,5,6]
var z = [x,y,x,y,x,y,x,y]

Tests:

lodash.flatMap
_.flatMap(z)
array.flatMap
z.flatMap(it => it)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash.flatMap
array.flatMap

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
lodash.flatMap	2935119.2 Ops/sec
array.flatMap	698290.6 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested in this benchmark.

**Overview**

The provided JSON represents two individual test cases, each measuring the performance of a different approach for flattening an array using JavaScript. The first test case uses Lodash's `flatMap` function, while the second test case uses the `flatMap` method of native arrays (i.e., `Array.prototype.flatMap`).

**Test Case 1: Lodash's `flatMap`**

In this test case, the script preparation code creates an array `z` that contains another array `[x, y, x, y, x, y, x, y]`. The benchmark definition is set to `_.flatMap(z)`, which means that the Lodash library's `flatMap` function will be called on the `z` array.

**Test Case 2: Native Array `flatMap`**

In this test case, the script preparation code creates an array `z` with the same structure as in Test Case 1. The benchmark definition is set to `z.flatMap(it => it)`, which means that a custom function will be used to flatten the array.

**Libraries and Libraries Purpose**

The Lodash library is being used in this test case, specifically its `flatMap` function. Lodash is a popular JavaScript utility library that provides a wide range of functions for common tasks, such as string manipulation, array and object manipulation, and more. In this context, the `flatMap` function is used to flatten an array.

**JavaScript Features and Syntax**

This benchmark does not explicitly use any special JavaScript features or syntax. However, it does demonstrate the difference between using a library (Lodash) versus native JavaScript methods (`Array.prototype.flatMap`) for flattening arrays.

**Performance Comparison**

The performance comparison is between two approaches:

1. Lodash's `flatMap` function
2. Native Array `flatMap` method

The pros and cons of each approach are as follows:

* **Lodash's `flatMap`**: Pros:
	+ More concise code
	+ Easier to read and maintain, especially for complex flattening tasks
	+ Reduces the risk of manual indexing errors
* Cons:
	+ Requires an external library (Lodash) to be included in the test environment
	+ May introduce additional overhead due to the size of the library
* **Native Array `flatMap`**: Pros:
	+ No external dependencies or library inclusion required
	+ Can be more efficient for simple flattening tasks
	+ Uses native code, which may be faster and more optimized
* Cons:
	+ Requires manual handling of indexing errors
	+ May require more complex code and maintenance

**Alternatives**

Other alternatives for flattening arrays include:

1. `Array.prototype.map().flat()` (ECMAScript 2019+): This method can flatten an array, but it may not be as efficient as native `flatMap` for large datasets.
2. `Array.prototype.reduce()`: While not specifically designed for flattening arrays, `reduce()` can be used to accumulate values from a nested array structure.
3. Custom implementation using `for...of` loops or recursive functions: These approaches require manual handling of indexing errors and may be less efficient than native methods.

In conclusion, this benchmark provides a useful comparison between two approaches for flattening arrays in JavaScript: Lodash's `flatMap` function versus the native Array `flatMap` method. The choice of approach depends on the specific requirements of the application, including performance, code complexity, and maintainability considerations.

Related benchmarks:

lodash flatmap vs array.flatMap fixed (version: 0)

Comparing performance of: lodash.flatMap vs array.flatMap

Created: 3 years ago by: Guest

Jump to the latest result

lodash.flatMap

array.flatMap

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):