Overview of the Benchmark

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided JSON represents a benchmark with two test cases: Reverse array / reverse vs map. This benchmark tests the performance of reversing an array in place versus using the map() method.

Test Cases

There are two test cases:

1. ES Reverse / in place: This test case uses the reverse() method to reverse the array in place.
2. ES map: This test case uses the map() method with a callback function to create a new array with the reversed elements.

Options Compared

The two test cases are compared in terms of their performance on reversing an array.

Pros and Cons of Different Approaches

1. In-Place Reversal (ES Reverse):
   • Pros: It modifies the original array, so it only requires a single memory allocation.
   • Cons: It can be slower than creating a new array due to the overhead of modifying the existing array.
2. Creating a New Array with map (ES Map):
   • Pros: It creates a new array, which can be faster than in-place reversal for large arrays.
   • Cons: It requires additional memory allocation and copying of elements.

Library Used

The map() method is used with a callback function to create a new array. The library used here is the built-in JavaScript Array.prototype.map() method.

Special JS Features or Syntax

None mentioned in this benchmark.

Other Alternatives

There are other alternatives for reversing an array, such as:

1. Using slice(), concat(), and reverse(): This approach creates a new array by concatenating the reversed elements.
2. Using a loop: A simple loop can be used to reverse an array in place.
3. Using reduce(): An array can be reversed using the reduce() method, which is less common than other methods.

Benchmark Preparation Code

The provided JSON includes two scripts:

1. test = [\"a\", \"b\", \"c\", \"d\", \"e\"];: Creates an array of strings.
2. No HTML preparation code is provided.

Latest Benchmark Result

The latest benchmark result shows the performance of both test cases on a specific browser (Chrome 127) and device platform (Desktop). The results are:

• ES Reverse / in place: 3,859,801 executions per second
• ES Map: 1,483,106.125 executions per second

These results suggest that in-place reversal (ES Reverse) is faster than creating a new array with map() (ES Map) on this specific hardware and software configuration.