Benchmark: Lodash Flatten v.s. concat

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

let ary = [1, [2, [3]]]

Tests:

Lodash Flatten
let ary = [1, [2, [3]]] return _.flatten(ary)
concate
let ary = [1, [2, [3]]] let res = [] ary.forEach(item => { if(!Array.isArray(item)) res.push(i) else res = res.concat(i) }); return res

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash Flatten
concate

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser/OS: Chrome 121 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Lodash Flatten	11907943.0 Ops/sec
concate	4639253.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark compares two approaches to flattening an array in JavaScript: using Lodash's `flatten` function and manually concatenating elements using a loop. The goal is to determine which approach is faster on modern JavaScript engines.

**Test Cases**

There are two test cases:

1. **Lodash Flatten**: This test case uses the `flatten` function from Lodash, a popular utility library for functional programming in JavaScript.
2. **Concated**: This test case manually concatenates elements using a loop, without relying on any external libraries.

**Library: Lodash**

Lodash is a JavaScript library that provides a wide range of useful functions for tasks like array manipulation, object creation, and more. The `flatten` function in particular is designed to recursively flatten arrays into single-level arrays.

In the context of this benchmark, using Lodash's `flatten` function simplifies the flattening process by handling nested arrays automatically. This can be beneficial for code readability and maintainability, as it reduces the need for manual looping or recursive functions.

**Pros of Using Lodash's Flatten Function:**

* Simplifies array flattening logic
* Reduces boilerplate code
* Handles nested arrays recursively

**Cons of Using Lodash's Flatten Function:**

* Adds external library dependency (Lodash)
* May introduce overhead due to the library's complexity
* Might not optimize for all possible use cases

**Manual Concatenation Approach (Concated)**

The concated approach manually concatenates elements using a loop, which can be less elegant and more error-prone than using Lodash's `flatten` function.

Pros of Manual Concatenation:

* No external library dependency
* May optimize for specific use cases or edge cases

Cons of Manual Concatenation:

* Requires manual looping and recursion
* More prone to errors due to the complexity of the logic
* Less readable and maintainable code

**Other Considerations**

In modern JavaScript engines, such as those used in browsers and Node.js, the performance difference between these two approaches may be negligible. However, for certain use cases or specific requirements (e.g., server-side rendering, game development), one approach might be more suitable than the other.

When to prefer Lodash's `flatten` function:

* When readability and maintainability are essential
* When working with large datasets or complex nested arrays
* When performance is not a top priority

When to prefer manual concatenation (concated):

* When no external library dependency is required
* When optimization for specific use cases or edge cases is necessary
* When performance is critical and every microsecond counts

**Alternatives**

Other alternatives for array flattening in JavaScript include:

1. **Array.prototype.flat()**: A more modern approach introduced in ECMAScript 2019, which provides a simpler and more efficient way to flatten arrays.
2. **Array.prototype.reduce()**: Can be used to flatten arrays by reducing the array elements into a single value.
3. **For...of loops**: Can be used to manually iterate over array elements and concatenate them.

These alternatives might offer better performance or readability than the Lodash `flatten` function, but they require more manual effort and expertise.

Related benchmarks:

Lodash Flatten v.s. concat (version: 0)

Comparing performance of: Lodash Flatten vs concate

Created: 5 years ago by: Guest

Jump to the latest result

Lodash Flatten

concate

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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