Overview

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided JSON represents a benchmark that compares the performance of three different methods for creating deep copies of objects: JSON.stringify, structuredClone, and _cloneDeep from the Lodash library.

Tested Options

The benchmark tests the execution speed of each method in creating deep copies of an object (MyObject). The options being compared are:

1. JSON.stringify: This method converts a JavaScript value to a JSON string, which can be used to create a copy of the original object.
2. structuredClone: This method creates a shallow clone of an object, and then recursively clones its values to create a deep copy.
3. _.cloneDeep from Lodash: This function is designed specifically for creating deep copies of objects.

Pros and Cons

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

1. JSON.stringify:
   • Pros: Simple, widely supported, and fast.
   • Cons: May not work correctly with certain data types (e.g., dates), and can be slow for very large objects.
2. structuredClone:
   • Pros: Fast, modern, and supports most data types.
   • Cons: Not yet widely supported in older browsers or versions of JavaScript.
3. _.cloneDeep from Lodash:
   • Pros: Designed specifically for creating deep copies, handles complex data structures well.
   • Cons: Requires the Lodash library, which may not be included in all projects.

Library and Its Purpose

The structuredClone method is a modern JavaScript function introduced in ECMAScript 2020 (ES10). It's designed to create shallow clones of objects, with the intention of eventually supporting deep cloning. The _cloneDeep function from Lodash provides a more robust implementation for creating deep copies.

Special JS Feature or Syntax

None mentioned in this benchmark.

Other Considerations

When choosing between these methods, consider the following:

• If you need to support older browsers or versions of JavaScript, JSON.stringify might be a safer choice.
• For modern, fast execution and support for most data types, structuredClone is likely the best option.
• If you're already using Lodash in your project, _cloneDeep provides a convenient and efficient solution.

Alternatives

If you don't want to use Lodash or prefer not to rely on modern JavaScript features, you can consider alternative methods for creating deep copies:

1. Array.prototype.slice(): While not as robust as structuredClone, this method can be used to create shallow clones of arrays.
2. For...in loops and Object.assign(): This approach requires more manual effort but can be effective for small objects.
3. Recursive functions: You can write your own recursive function to clone an object, which can be a good learning exercise.

However, these alternatives may not be as efficient or reliable as structuredClone and _cloneDeep.