Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

Benchmark Overview

The benchmark compares two approaches to create a copy of an object in JavaScript: structuredClone and spread syntax ({ ...voucher }). The goal is to determine which approach is faster, more efficient, or both.

Options Compared

There are two options being compared:

1. window.structuredClone(voucher): This method uses the structuredClone function, introduced in JavaScript 2020, to create a deep copy of the object voucher. The structuredClone function is designed to produce an exact clone of the original object, including its internal properties and references.
2. Spread syntax ({ ...voucher }): This method uses the spread operator (...) to create a shallow copy of the object voucher. The resulting object will have all the same properties as the original object, but any nested objects or arrays may not be copied recursively.

Pros and Cons

• structuredClone(voucher):
  • Pros: Produces an exact clone of the original object, including internal properties and references. This can be useful in scenarios where preserving the original structure is crucial.
  • Cons: May be slower than spread syntax due to the overhead of creating a deep copy.
• Spread syntax ({ ...voucher }):
  • Pros: Faster than structuredClone because it only creates a shallow copy, which requires less work.
  • Cons: Does not preserve internal properties and references, so changes made to nested objects or arrays may affect the original object.

Library/Feature

There is no library being used in this benchmark. However, structuredClone is a built-in JavaScript feature introduced in 2020, making it a part of the language itself.

Special JS Feature/Syntax

The benchmark uses the structuredClone function, which was introduced as a proposed feature in ECMAScript 2020 and later adopted as a standard. The spread syntax ({ ...voucher }) is also a built-in JavaScript feature that has been available since ECMAScript 2015.

Other Alternatives

If you're interested in exploring other approaches to create copies of objects, here are some alternatives:

• Using the JSON.parse(JSON.stringify(voucher)) method (shallow copy)
• Using a library like Lodash's cloneDeep() function (deep copy)
• Using a recursive function to manually clone the object (custom implementation)

Keep in mind that each approach has its own trade-offs and may not be suitable for all use cases.

I hope this explanation helps you understand the benchmark and the options being compared!