Benchmark: for loop array - MeasureThat.net

Script Preparation code:

var array = [];
for(let i = 0; i < 10; i++) {
	array.push(i);
}

Tests:

for
for(let i = 0; i < array.length; i++) { let el = array[i]; }
for of
for(let el of array) { }
for each
array.forEach(el => { });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
for of
for each

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is an essential task, and MeasuringThat.net provides a great platform for it. Let's break down the benchmark definition and test cases to understand what's being tested.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark that tests different approaches for iterating over arrays. The benchmark definition consists of three parts:

1. **Script Preparation Code**: This is a snippet of JavaScript code that sets up an empty array `array` and populates it with 10 elements using a traditional `for` loop.
2. **Html Preparation Code**: This is currently empty, but it might be used to set up some HTML environment or dependencies for the benchmark.

**Test Cases**

The test cases are individual iterations of the benchmark that compares different approaches for iterating over the populated array:

1. **Traditional "for" loop**: The benchmark definition uses a traditional `for` loop with an index variable `i` to iterate over the array elements.
2. **"For of" loop**: This is a newer, more concise way of iterating over arrays using the `for...of` loop syntax. It's designed for iterating over arrays and other iterable objects.
3. **`.forEach()` method**: The benchmark also tests the `.forEach()` method, which is another common way to iterate over array elements.

**Pros and Cons**

Each approach has its pros and cons:

* Traditional "for" loop:
	+ Pros: More control over the iteration process, can be used for arrays and other iterable objects.
	+ Cons: Can be slower due to the overhead of explicit index management.
* "For of" loop:
	+ Pros: Concise syntax, faster execution since it doesn't require manual index management.
	+ Cons: Limited control over the iteration process, only suitable for iterating over arrays and other iterable objects.
* `.forEach()` method:
	+ Pros: Simple syntax, efficient execution since it's optimized for array iteration.
	+ Cons: Limited control over the iteration process, can be slower than "for of" loop due to additional overhead.

**Library Usage**

There is no explicit library usage in this benchmark definition. However, if you notice any differences between browsers or devices, it might be related to differences in JavaScript engine optimizations or implementations.

**Special JS Features or Syntax**

There are some special features used here:

* The `.forEach()` method is a built-in JavaScript method that's widely supported across modern browsers and engines.
* The "For of" loop syntax is a newer feature introduced in ECMAScript 2015 (ES6). It's designed to simplify iterating over arrays, but might not work in older browsers or engines.

**Alternatives**

If you're interested in testing other approaches for iterating over arrays, here are some alternatives:

* **`while` loop**: A traditional loop that uses a variable to keep track of the iteration index.
* **`.map()` method**: While primarily designed for array transformations, `.map()` can also be used as an alternative iteration approach using the `forEach` callback function.
* **Generators or iterators**: More advanced approaches that use generators or iterators to control iteration over arrays.

Keep in mind that these alternatives might not be as efficient or convenient as the traditional "for" loop, ".forEach()" method, or "For of" loop. However, they can provide additional insights into different iteration strategies and their performance characteristics.

Related benchmarks:

for loop array (version: 0)

Comparing performance of: for vs for of vs for each

Created: 3 years ago by: Guest

Jump to the latest result

for

for of

for each

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):