Benchmark: Lodash _.union vs native Set() 2

HTML Preparation code:

<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/lodash@4.17.10/lodash.min.js"></script>

Script Preparation code:

var a = [1, 2, 3, 4, 5, 4, 5, 2, 7, 9, 10, 11, 15, 17, 3, 16, 23]
var b = [3, 4, 5, 6, 7, 10, 23, 5049, 194, 39 ]

Tests:

_.union
var c = _.union(a, b)
Set()
var c = new Set(a, b)
Set() convert back to array
var c = new Set(a, b) var d = Array.from(c)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
_.union
Set()
Set() convert back to array

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and its results.

**What is tested on the provided JSON?**

The provided JSON represents three microbenchmarks that compare the performance of different approaches for creating a union of two arrays in JavaScript:

1. `_.union` from Lodash library
2. Native `Set()` data structure (without converting it back to an array)
3. Native `Set()` data structure with conversion back to an array using `Array.from()`

**Options compared**

The three options are compared as follows:

* `_.union`: A function provided by the Lodash library that creates a new set-like object with all elements from both arrays.
* Native `Set()`: A built-in JavaScript data structure that can be used to create a set of unique values.
* Native `Set()` + `Array.from()`: Converting the resulting set back to an array using the `Array.from()` method.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. `_.union` from Lodash library:
	* Pros: Easy to use, provides a convenient function for creating sets.
	* Cons: Adds overhead due to the use of an external library.
2. Native `Set()`: Fastest option (without conversion)
	* Pros: Built-in JavaScript data structure, fast performance.
	* Cons: Requires manual handling of duplicate values.
3. Native `Set()` + `Array.from()`: Slightly slower than native `Set()`, but eliminates manual handling of duplicates.
	* Pros: Eliminates need for manual handling of duplicates.
	* Cons: Adds slight overhead due to the use of `Array.from()`.

**Library and its purpose**

The Lodash library provides a range of utility functions, including `_union`, which can be useful when working with arrays or sets in JavaScript. The library's purpose is to provide a set of reusable functions that can simplify code and improve performance.

**Special JS feature or syntax**

None mentioned in the provided benchmark JSON.

**Other alternatives**

If you prefer not to use a library like Lodash, you could consider implementing your own union function using native JavaScript data structures, such as `Set()` and `Array.prototype.forEach()`. However, this approach would likely be slower than using `_.union` from Lodash or the native `Set()` + `Array.from()` approach.

In summary, the provided benchmark compares three approaches for creating a union of two arrays in JavaScript: Lodash's `_union` function, native `Set()` data structure, and native `Set()` with conversion back to an array using `Array.from()`. The results show that native `Set()` is generally the fastest option, followed by the native `Set()` + `Array.from()` approach.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36

Browser/OS: Chrome 74 on Windows

View result in a separate tab

Test name	Executions per second
_.union	1223892.2 Ops/sec
Set()	1463455.4 Ops/sec
Set() convert back to array	1137370.4 Ops/sec

Related benchmarks:

Lodash _.union vs native Set() 2 (version: 0)

Comparing performance of: _.union vs Set() vs Set() convert back to array

Created: 5 years ago by: Guest

Jump to the latest result

_.union

Set()

Set() convert back to array

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):