I'd be happy to help you understand the JavaScript benchmark on MeasureThat.net.

Benchmark Overview

The benchmark compares two ways to check if a string ends with a specific suffix: string.endsWith() and string.slice() + ===. The benchmark is designed to measure which approach is faster, more efficient, and possibly more accurate for this specific use case.

Options Compared

Two options are compared:

1. string.endsWith(comparator): This method checks if the string ends with the specified suffix (comparator).
2. string.slice(-comparator.length) === comparator: This approach uses the slice() method to extract a substring from the end of the original string, and then compares it directly to the comparator using the === operator.

Pros and Cons

1. string.endsWith(comparator):
   • Pros: More readable, concise, and efficient (as it's implemented in native code).
   • Cons: May not be as performant for very large strings due to its dynamic nature.
2. string.slice(-comparator.length) === comparator:
   • Pros: Can be more performant for large strings, as it avoids the overhead of a dynamic method call.
   • Cons: Less readable and more verbose, which can make the code harder to maintain.

Library

There is no library explicitly mentioned in this benchmark. However, string.endsWith() is an intrinsic JavaScript method that's implemented by most modern browsers and Node.js environments.

Special JS Feature or Syntax

This benchmark does not use any special JavaScript features or syntax beyond what's standard in JavaScript (ECMAScript).

Benchmark Preparation Code

The preparation code defines two functions:

• compareEndsWith(val, comparator): This function checks if the string val ends with the specified suffix (comparator) using the endsWith() method.
• compareSliceMethod(val, comparator): This function uses the slice() method to extract a substring from the end of the original string and compares it directly to the comparator using the === operator.

Other Alternatives

In theory, other approaches could be used to check if a string ends with a specific suffix, such as:

• Using a regular expression: RegExp.prototype.test(val, new RegExp(^.*${comparator}$, 'g'))
• Implementing a custom function using bitwise operations and string manipulation
• Using a library like Lodash or Underscore.js

However, these alternatives are not part of the benchmark and may not be as efficient, readable, or maintainable as the two options being compared.

I hope this explanation helps! Let me know if you have any further questions.