Let's dive into the world of MeasureThat.net and explore what's being tested in this benchmark.

What is being tested?

The provided JSON represents two test cases, each measuring the performance difference between null and undefined when used as a default value in a JavaScript context. The tests are designed to evaluate which one is more efficient in terms of execution speed.

Options compared: null vs undefined

In this benchmark, we have two options being compared:

1. Null (null): In JavaScript, null represents the absence of any object value. It's often used as a placeholder or default value.
2. Undefined (undefined): In JavaScript, undefined is a primitive value that indicates an uninitialized variable or a variable that has been declared but not assigned a value.

Pros and Cons of each approach:

• Null (null):
  • Pros:
    • More predictable behavior in some cases (e.g., when using the === null equality operator).
    • Can be easier to work with, especially for developers who are accustomed to working with null values.
  • Cons:
    • May lead to confusing code if not handled carefully (e.g., checking for null instead of undefined).
• Undefined (undefined):
  • Pros:
    • More intuitive behavior in some cases (e.g., when using the === undefined equality operator).
    • Can make code more readable, especially when explicitly indicating an uninitialized variable.
  • Cons:
    • May lead to unexpected behavior if not handled carefully.

Other considerations:

• Library usage: None of the test cases use any libraries or external dependencies.
• Special JS features or syntax: The benchmark uses ES6-style syntax (let, for loops) but does not include any experimental or esoteric features that might affect performance.

Alternatives:

To perform similar benchmarks, developers can experiment with other values, such as:

• Empty strings ("")
• Zero (0)
• Falsey values (e.g., false, NaN, Infinity)

Keep in mind that the results may vary depending on the specific use case and JavaScript engine being used.

By running these benchmarks, MeasureThat.net provides valuable insights into the performance characteristics of different default value options in JavaScript, which can inform coding decisions and help developers optimize their code for better performance.