Benchmark: isUnique (Lodash uniqBy vs Set)

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.20/lodash.min.js'></script>

Script Preparation code:

var MyArr = Array.from({
    length: 40
}, () => ({
    x: Math.floor(Math.random() * 40)
}));

function isUniqueLodashUniqBy(arr) {
    return arr.length === _.uniqBy(arr, it => it.x);
}

function isUniqueSet(arr) {
    return arr.length === new Set(arr.map(it => it.x)).size;
}

Tests:

Lodash uniqBy
isUniqueLodashUniqBy(MyArr);
Set
isUniqueSet(MyArr);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash uniqBy
Set

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; rv:105.0) Gecko/20100101 Firefox/105.0

Browser/OS: Firefox 105 on Windows

View result in a separate tab

Test name	Executions per second
Lodash uniqBy	670240.9 Ops/sec
Set	452422.7 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The website provides a JSON object that represents the benchmark definition. Here, we have two test cases:

1. `isUniqueLodashUniqBy(arr)`: This function uses Lodash's `uniqBy` method to check if all elements in an array are unique based on their values. The `_` variable is likely referring to the root namespace of Lodash.
2. `isUniqueSet(arr)`: This function uses a JavaScript Set data structure to check if all elements in an array are unique.

**Options Compared**

The two functions are being compared for performance differences:

* **Lodash's `uniqBy` method**: This is a utility function that recursively checks each element of the array to see if it matches any other element. It's designed to handle nested objects.
* **JavaScript Set data structure**: A Set in JavaScript is a collection of unique values. When you add an element to a Set, and that element already exists in the Set, nothing happens.

**Pros and Cons**

Here are some pros and cons for each approach:

* **Lodash's `uniqBy` method**:
	+ Pros: Handles nested objects and can be more convenient to use when working with complex data structures.
	+ Cons: Can be slower due to recursive checks and the overhead of the Lodash library.
* **JavaScript Set data structure**:
	+ Pros: Fast, efficient, and optimized for performance. No additional libraries or dependencies are needed.
	+ Cons: May not handle nested objects well (although this can often be a deliberate design choice).

**Library and Purpose**

The `lodash` library is a popular JavaScript utility library that provides a wide range of functional programming helpers, including the `uniqBy` method.

In this benchmark, Lodash's `uniqBy` method is being used to test its performance in comparison to a plain JavaScript Set data structure. The purpose of this benchmark is likely to determine which approach is faster and more efficient for similar tasks.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntaxes mentioned in the benchmark definition that require explanation.

**Other Alternatives**

If you need to check if all elements in an array are unique, there are other alternatives besides Lodash's `uniqBy` method and a plain JavaScript Set:

* **Using a Map**: You can use a Map to store unique values from the array. Since Maps cannot have duplicate keys, this approach is essentially equivalent to using a Set.
* **Using a custom implementation**: You could write a simple custom function to iterate through the array and check for duplicates.

However, these alternatives are not mentioned in the benchmark definition provided.

Related benchmarks:

isUnique (Lodash uniqBy vs Set) (version: 0)

Comparing performance of: Lodash uniqBy vs Set

Created: 4 years ago by: Guest

Jump to the latest result

Lodash uniqBy

Set

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):