Benchmark: Lodash Difference vs. Filter

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 = ["America", "Brazil", "China", "Denmark", "Equador", "Finland", "Germany", "Haiti", "Indonesia", "Japan", "Kiribati"]
var b = ["Haiti", "Indonesia", "Japan", "Kiribati"]

Tests:

Lodash
var c = _.difference(a, b)
Filter
var c = a.filter(x => b.includes(x));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash
Filter

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 14 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Linux

View result in a separate tab

Test name	Executions per second
Lodash	4672533.0 Ops/sec
Filter	12574045.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 14 days ago):

LLMs can make mistakes. Check important info.

The benchmark you provided compares two different approaches for finding the difference between two arrays: using the Lodash library and using the native JavaScript `Array.prototype.filter` method combined with the `Array.prototype.includes` method. Here's a detailed analysis of the benchmark setup, including the options compared, their pros and cons, and other considerations.

### Options Compared

1. **Lodash (`_.difference`)**:
   - **Implementation**: This method is part of the Lodash library, which is a modern utility library that provides various functions for common programming tasks, such as manipulating arrays, objects, and more.
   - **Expression**: `var c = _.difference(a, b);`
   - **Description**: The `difference` function takes two arrays and returns a new array containing the elements of the first array that are not present in the second array.

2. **Native Filter Method**:
   - **Implementation**: This utilizes the built-in `Array.prototype.filter` method in combination with `Array.prototype.includes`.
   - **Expression**: `var c = a.filter(x => b.includes(x));`
   - **Description**: The `filter` method creates a new array with all elements that pass the test implemented by the provided function. Here, it checks if each element in array `a` is included in array `b`.

### Performance Results

According to the benchmark results, the native JavaScript `filter` method outperformed the Lodash implementation significantly.

- **Executions per Second for `Filter`**: 12,574,045
- **Executions per Second for `Lodash`**: 4,672,533

### Pros and Cons

**Lodash (`_.difference`)**:
- **Pros**:
  - **Simplicity**: The intent of the code is more declarative and easier to read, especially for those familiar with Lodash.
  - **Robustness**: Lodash functions are well-tested and optimized for various edge cases.
- **Cons**:
  - **Performance**: In this instance, it is slower compared to native solutions.
  - **Dependency**: Requires including an external library, increasing the size of the bundle if used in a web application.

**Native Filter Method**:
- **Pros**:
  - **Performance**: Faster execution in this benchmark, which can lead to better overall application performance when operating on large datasets.
  - **No External Dependency**: Uses native JavaScript, enhancing portability and reducing bundle size.
- **Cons**:
  - **Complexity**: The code may be less readable for developers unfamiliar with the `filter` and `includes` methods or JavaScript arrow functions.

### Other Considerations

- **Readability vs. Performance**: Choosing between a utility library like Lodash and native JavaScript often boils down to whether readability or performance is the primary concern. For smaller datasets or less performance-critical applications, the readability of Lodash might be favored.
  
- **Type Checking**: Lodash provides type-checking functionality, which can prevent runtime errors that might not be immediately evident with native methods. This can be particularly valuable in larger codebases.

- **Browser Support**: While Lodash works across all browsers, leveraging native methods can sometimes lead to better performance and less overhead in modern browsers, which optimize built-in functions.

### Alternatives

Other alternatives for achieving similar outcomes could include:

1. **Using `Set`**: You could convert one of the arrays to a `Set` and filter the other array based on that:
   ```javascript
   const setB = new Set(b);
   var c = a.filter(x => !setB.has(x));
   ```
   This approach can improve performance further, especially with larger datasets since `Set` lookups are generally O(1) time complexity.

2. **For Loop**: A traditional `for` loop can also be used, which provides full control over iteration and condition checking. This can often be more performant than higher-order functions:
   ```javascript
   var c = [];
   for (var i = 0; i < a.length; i++) {
       if (!b.includes(a[i])) {
           c.push(a[i]);
       }
   }
   ```

In summary, this benchmark showcases the performance differences between the use of an external utility library and native JavaScript methods, emphasizing the trade-offs in readability, maintainability, and performance. The results strongly indicate that for this specific use case, the native implementation is preferable.

Related benchmarks:

Lodash Difference vs. Filter (version: 1)

Comparing performance of: Lodash vs Filter

Created: 14 days ago by: Registered User

Jump to the latest result

Lodash

Filter

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 14 days ago):