Benchmark: for-of-foreach-1

Script Preparation code:

function generateTestArray() {
  const result = [];
  for (let i = 0; i < 1000000; ++i) {
    result.push(i);
  }
  return result;
}

Tests:

foeach
const array = generateTestArray(); array.forEach(v => { var a = v });
forof
const array = generateTestArray(); for (const v of array) { const a = v }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
foeach
forof

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
foeach	47.1 Ops/sec
forof	47.9 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to help explain the benchmark.

**Overview**

The provided JSON represents two test cases, `for-of-foreach-1`, which measure the performance of JavaScript's `for...of` loop and traditional `forEach()` method.

**Options Compared**

The benchmark compares the performance of two approaches:

1. **Traditional `forEach()` method**: This involves using a callback function to iterate over an array.
2. **New `for...of` loop**: This is a new syntax introduced in ECMAScript 2015 (ES6) that allows iterating over arrays using a simple, loop-like structure.

**Pros and Cons of Each Approach**

1. **Traditional `forEach()` method**:
	* Pros: Simple to implement, widely supported, and easy to read.
	* Cons: Can be slower than the new `for...of` loop due to the overhead of function calls and context switching.
2. **New `for...of` loop**:
	* Pros: Generally faster than traditional `forEach()` method, as it avoids the overhead of function calls and can be optimized for performance.
	* Cons: May require more code to implement, and its syntax is not yet widely adopted.

**Library Usage**

There is no explicit library usage in these benchmark definitions. However, the `generateTestArray()` function used in both test cases creates a large array using an arrow function, which suggests that the benchmark is designed to focus on the performance of JavaScript's built-in features rather than external libraries.

**Special JavaScript Features/Syntax**

The benchmark uses ES6+ syntax, specifically the new `for...of` loop. This feature was introduced in ECMAScript 2015 (ES6) and allows iterating over arrays using a simple, loop-like structure.

**Other Alternatives**

If you were to implement this benchmark yourself, you could also consider testing other approaches, such as:

* **Using `Array.prototype.forEach()` with an arrow function**: This would be similar to the traditional `forEach()` method used in the benchmark.
* **Using `for` loops with index variables**: This would require using a different syntax and may not provide the same performance benefits as the new `for...of` loop.

To create this benchmark, you could write JavaScript code that creates an array using one of these approaches and then measures the time it takes to iterate over the array using each method. The results would be comparable to those provided by MeasureThat.net.

Related benchmarks:

for-of-foreach-1 (version: 0)

Comparing performance of: foeach vs forof

Created: one year ago by: Guest

Jump to the latest result

foeach

forof

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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