What is being tested?

The benchmark tests the performance of two approaches to remove undefined values from an array: the _.compact() function from the Lodash library, and the array.filter(Boolean) method.

Options compared

There are two options being compared:

1. _.compact(): This function returns a new array with all elements removed that are equal to undefined.
2. Array.prototype.filter(Boolean): This method creates a new array with all elements that pass the test implemented by the provided function.

Pros and Cons of each approach

_.compact()

Pros:

• More concise and readable code
• Lodash library provides a well-maintained and widely-used implementation

Cons:

• May have additional overhead due to the use of a separate library
• May not be as well-optimized for performance compared to native JavaScript methods

Array.prototype.filter(Boolean)

Pros:

• Native JavaScript method, potentially more efficient and lightweight
• Does not require an external library

Cons:

• More verbose code
• Requires understanding of the Boolean context function in JavaScript

Other considerations

Both approaches can be effective, but the choice between them depends on the specific use case and performance requirements. If readability and convenience are more important than raw performance, _.compact() might be a better choice. However, if every ounce of performance counts, using native JavaScript methods like filter(Boolean) could be a better option.

Library explanation

The Lodash library is a popular collection of functional programming utilities in JavaScript. It provides many useful functions for tasks such as array manipulation, object iteration, and more. In this benchmark, the _.compact() function is used to remove undefined values from an array.

Special JS feature or syntax

No special JavaScript features or syntax are being tested in this benchmark. The code snippets provided use standard JavaScript syntax and methods.

Benchmark preparation code explanation

The script preparation code creates an array with undefined values, which will be used as input for both tests: _.compact() and array.filter(Boolean).