Benchmark: KeithTest - MeasureThat.net

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

Tests:

for
for (var i = 0; i < arr.length; i++) { console.log(arr[i]); }
forin
for (var i in arr) { console.log(i); }
forof
for (var i of arr) { console.log(i); }
foreach
_.forEach(arr, function (i) { console.log(i); })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
forin
forof
foreach

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.67 Safari/537.36 Edg/87.0.664.52

Browser/OS: Chrome 87 on Windows

View result in a separate tab

Test name	Executions per second
for	225.2 Ops/sec
forin	247.5 Ops/sec
forof	246.2 Ops/sec
foreach	275.9 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition JSON**

The provided Benchmark Definition JSON defines a set of tests to measure the performance of different loop iteration methods in JavaScript. The benchmark consists of four test cases:

1. `for` loop
2. `for...in` loop (also known as the "legacy" for loop)
3. `for...of` loop (a newer iteration method introduced in ECMAScript 2015)
4. `_` (Lodash) `forEach` function

Each test case has a unique name and a benchmark definition script that contains the code to be executed.

**Options Compared**

The four options compared are:

1. **Classic `for` loop**: A traditional loop iteration method using the `var i = 0; while (i < arr.length) { ... }` approach.
2. **Legacy `for...in` loop**: An older iteration method that uses the `for (var i in arr)` syntax to iterate over the array's properties.
3. **Newer `for...of` loop**: A more modern iteration method introduced in ECMAScript 2015, which uses the `for (const i of arr)` syntax to iterate over the array's elements.
4. **Lodash `forEach` function**: A utility library function that provides a convenient way to execute a callback function on each element of an array.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Classic `for` loop**:
	+ Pros: Simple, widely supported, and easy to understand.
	+ Cons: May not be as efficient or concise as newer iteration methods.
* **Legacy `for...in` loop**:
	+ Pros: Still widely used and understood, especially in older JavaScript versions.
	+ Cons: Can lead to unexpected behavior if not used carefully (e.g., iterating over object properties instead of array elements).
* **Newer `for...of` loop**:
	+ Pros: More concise and expressive than traditional loops, with better support for iterators.
	+ Cons: May require a brief learning curve for developers familiar with older iteration methods.
* **Lodash `forEach` function**:
	+ Pros: Provides a convenient and flexible way to execute a callback function on each element of an array.
	+ Cons: Introduces additional dependencies (Lodash) and may not be as optimized as native loop implementations.

**Library Usage**

The Lodash `forEach` function is used in the benchmark, which requires including the Lodash library in the test environment. The `_.forEach` function takes two arguments: the array to iterate over (`arr`) and a callback function that will be executed for each element.

**Special JS Features or Syntax**

None of the provided benchmark cases explicitly utilize any special JavaScript features or syntax beyond what's commonly used in web development.

**Other Alternatives**

If you're looking for alternative loop iteration methods, consider:

* **`Array.prototype.forEach`**: A built-in method that provides a similar interface to Lodash's `forEach`, but with less dependencies.
* **`Array.prototype.map()`**: While not a direct equivalent, the `map()` method can be used in combination with other array methods to achieve loop-like behavior.

Keep in mind that these alternatives might require different code structures or additional dependencies, so choose the best approach based on your specific use case and requirements.

Related benchmarks:

KeithTest (version: 0)

KeithTest

Comparing performance of: for vs forin vs forof vs foreach

Created: 4 years ago by: Guest

Jump to the latest result

for

forin

forof

foreach

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):