Benchmark: uniq vs new Set()

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/g/lodash@4(lodash.min.js+lodash.fp.min.js)"></script>

Script Preparation code:

const numbers = [1, 2, 2, 3, 4, 4, 5];

Tests:

_.uniq(numbers)
const uniqueNumbers = _.uniq(numbers);
Array.from(new Set(numbers))
const uniqueNumbers = Array.from(new Set(numbers));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
_.uniq(numbers)
Array.from(new Set(numbers))

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
_.uniq(numbers)	29567658.0 Ops/sec
Array.from(new Set(numbers))	11898166.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one year ago):

LLMs can make mistakes. Check important info.

The benchmark you provided compares two different approaches for obtaining unique values from an array of numbers in JavaScript. The specific case in focus is the array `numbers`, which contains duplicate values: `[1, 2, 2, 3, 4, 4, 5]`. Here's a description of the two options being tested, their pros and cons, and some other considerations.

### Options Compared

1. **Using Lodash's `_.uniq` Method:**
   ```javascript
   const uniqueNumbers = _.uniq(numbers);
   ```

2. **Using Native JavaScript (`new Set()` with `Array.from`):**
   ```javascript
   const uniqueNumbers = Array.from(new Set(numbers));
   ```

### Pros and Cons

#### 1. **Lodash - `_.uniq(numbers)`**
   - **Pros:**
     - **Ease of Use:** Lodash provides a simple and intuitive API. It’s immediately clear that you want to derive unique values from an array using `_.uniq`.
     - **Performance with Large Datasets:** Lodash is highly optimized for performance in handling arrays and collections.
     - **Consistency:** Lodash handles edge cases and types consistently, which can be beneficial when working with complex datasets.

- **Cons:**
     - **Dependency:** Using Lodash adds a dependency to the project. This may increase the bundle size if not tree-shaken properly.
     - **Overhead:** For simple tasks, introducing an external library might introduce unnecessary complexity.

#### 2. **Native JavaScript (`Array.from(new Set(numbers))`)**
   - **Pros:**
     - **No External Dependencies:** This approach uses native JavaScript features, so there’s no need to include any additional libraries, resulting in a smaller bundle size.
     - **Modern Syntax:** Using `Set` is a clean and modern approach to achieve uniqueness in arrays.
     - **Performance:** In environments where native implementations are optimized, this could be very efficient.

- **Cons:**
     - **Complexity:** This approach may be slightly less readable for developers who are not familiar with `Set` and `Array.from`. It involves understanding how sets work and may be less intuitive to novice developers.
     - **Edge Cases:** If the array includes types that can't be properly compared (e.g., objects), the use of sets may not behave as expected without additional handling.

### Other Considerations

- **Performance Results:** From the benchmark results, we see an execution rate of approximately 29.56 million executions per second for `_.uniq(numbers)` compared to about 11.90 million for `Array.from(new Set(numbers))`. This indicates that the Lodash method could be significantly faster in this scenario, especially for larger datasets.
  
- **Browser Compatibility:** Both methods are supported in modern browsers, but npm libraries like Lodash may attract developers who value cross-browser compatibility and consistency over a certain range of environments.

### Alternatives

Other alternatives for achieving uniqueness in JavaScript arrays might include:

- **Using a Loop:** Implementing a loop with an accumulator to filter out duplicates manually. While this offers granular control, it's generally less efficient and more verbose.
- **Using `filter()`:** Combining `filter()` with `indexOf()` can achieve the same result, but it is less performant due to being O(n^2) in complexity.
  
Each of these methods has its own merit depending on the specific use case, dataset size, and required performance.

This benchmark comparison highlights the trade-offs between convenience and dependency management versus performance and code simplicity that software engineers should consider in their projects.

Related benchmarks:

uniq vs new Set() (version: 1)

Comparing performance of: _.uniq(numbers) vs Array.from(new Set(numbers))

Created: one year ago by: Guest

Jump to the latest result

_.uniq(numbers)

Array.from(new Set(numbers))

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one year ago):