Benchmark: forEach vs for of 7

Script Preparation code:

var arr = Array(10000000).fill(0);

Tests:

forEach
arr.forEach(item => item);
forOf
for (const item of arr) item;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
forEach
forOf

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36

Browser/OS: Chrome 124 on Windows

View result in a separate tab

Test name	Executions per second
forEach	10.7 Ops/sec
forOf	8.6 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks and explore what's being tested in this specific benchmark.

**What is being tested?**

The provided JSON represents a benchmark comparison between two approaches:

1. `forEach`: A traditional, iterative method that uses a callback function to process each item in an array.
2. `forOf`: A newer, more modern approach that uses a for-of loop to iterate over the array.

**What options are compared?**

The main options being compared are:

* **Array iteration**: The two methods are used to iterate over an array of 10 million elements (generated using `Array(10000000).fill(0)`).

**Pros and Cons of each approach:**

1. **forEach**:
	* Pros:
		+ Wide compatibility across browsers and platforms.
		+ Easy to understand and implement, especially for those familiar with callback functions.
	* Cons:
		+ Can be less efficient than `forOf` due to the overhead of function calls and argument passing.
2. **forOf**:
	* Pros:
		+ More modern and efficient approach, as it avoids the overhead of function calls and argument passing.
		+ Better suited for large datasets, as it can take advantage of caching mechanisms (if enabled).
	* Cons:
		+ Not yet widely supported by older browsers or platforms.

**Library usage:**

There is no explicit library mentioned in the benchmark definition. However, note that the `Array.prototype.forEach` method is a part of the ECMAScript standard, and its implementation can vary across browsers and platforms.

**Special JS feature or syntax:**

No special JavaScript features or syntax are used in this benchmark. The focus is solely on comparing two different iteration approaches.

**Other alternatives:**

If you're interested in exploring alternative array iteration methods, some examples include:

1. `map()`: A method that creates a new array with the results of applying a provided function to each element.
2. `filter()`: A method that creates a new array with only the elements that pass a test implemented by a provided function.
3. `reduce()`: A method that applies a function to each element in an array and reduces it to a single output value.

These alternatives can offer different trade-offs, such as performance, memory usage, or code readability, depending on your specific use case.

Related benchmarks:

forEach vs for of 7 (version: 0)

Comparing performance of: forEach vs forOf

Created: 2 years ago by: Guest

Jump to the latest result

forEach

forOf

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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