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

Benchmark Definition and Preparation Code

The benchmark definition is provided in JSON format, which describes the test being run on the website. Here's what we have:

• The Name field specifies the name of the benchmark: "delete vs spread need for speed".
• The Description field is empty, as there isn't a detailed description of the benchmark.
• The Script Preparation Code section sets up an object person with properties name, age, and sex. This will be used as input for the test cases.

Individual Test Cases

The benchmark consists of two individual test cases:

1. Test Case 1: "del"
   • The Benchmark Definition specifies the JavaScript code to run: delete person.name.
   • The purpose of this test is to measure the execution speed of deleting a property from an object using the delete keyword.
2. Test Case 2: "spread"
   • The Benchmark Definition specifies the JavaScript code to run: let { name, ...rest} = person;.
   • The purpose of this test is to measure the execution speed of destructuring a property from an object using the spread syntax ({...}).

Comparison and Options

The two approaches compared in these tests are:

1. Deleting a property directly: delete person.name
2. Destructuring a property with spread syntax: let { name, ...rest} = person;

These approaches have different pros and cons:

• Deleting a property directly:
  • Pros: Simple and straightforward.
  • Cons: May trigger garbage collection if the object is deleted, which can impact performance.
• Destructuring a property with spread syntax:
  • Pros: More efficient and less prone to garbage collection issues, as it only updates references to existing properties.
  • Cons: Requires more code and may be slower due to additional computation.

Library Usage

In this benchmark, there is no explicit library usage. However, some JavaScript engines (like V8 in Chrome or SpiderMonkey in Firefox) provide built-in support for various optimization techniques, such as:

• Garbage collection: Automatic memory management to prevent memory leaks.
• Just-In-Time (JIT) compilation: Compiling JavaScript code into native machine code for performance.

Special JS Feature/Syntax

This benchmark doesn't use any special or advanced JavaScript features like async/await, let Constants, or modern ES modules. The focus is on basic property deletion and destructuring operations.

Other Alternatives

If you're interested in exploring other microbenchmarking tools, here are some alternatives:

• jsperf: A classic JavaScript benchmarking tool that has been around since 2007.
• Benchmark.js: A popular JavaScript benchmarking library for Node.js applications.
• WebPerformance: Google's web performance testing tool, which includes a JavaScript benchmarking feature.

In summary, the "delete vs spread need for speed" benchmark on MeasureThat.net compares two basic approaches to deleting a property from an object in JavaScript: directly using delete and with the spread syntax. The tests aim to measure execution speeds and identify potential optimization techniques.