Benchmark: Do something with for vs foreach vs some vs for..of

Script Preparation code:

var array = new Array(100);
var result = []

Tests:

for
for (var i = 0; i < array.length; i++) { array[i]; }
foreach
array.forEach(function(i) { result.push(array[i]); });
some
array.some(function(i) { result.push(array[i]); });
for..of
for (var i of array) { result.push(array[i]); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
foreach
some
for..of

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36

Browser/OS: Chrome 86 on Linux

View result in a separate tab

Test name	Executions per second
for	64128.6 Ops/sec
foreach	3115551.5 Ops/sec
some	3490478.0 Ops/sec
for..of	41797.7 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided JSON data represents a benchmark comparison between four different loop approaches: `for`, `forEach`, `some`, and `for..of`. The goal is to determine which approach yields the best performance.

**Loop Approaches Compared**

1. **`for`**: This traditional loop uses an explicit index variable to iterate over the array.
2. **`forEach`**: This method iterates over the array using a callback function, where each iteration is passed as an argument.
3. **`some`**: This method returns `true` if any element in the array passes a test provided by a function, and `false` otherwise. In this benchmark, it's used to push elements to the result array.
4. **`for..of`**: This newer loop uses the `for...of` syntax to iterate over the array using an iterator.

**Pros and Cons of Each Approach**

1. **`for`**:
	* Pros: Simple and straightforward; easy to understand and maintain.
	* Cons: Can lead to off-by-one errors if not careful; index variables can be error-prone.
2. **`forEach`**:
	* Pros: Elegant and concise; no need to worry about indices.
	* Cons: May have performance implications due to the overhead of method calls.
3. **`some`**:
	* Pros: Can be useful when working with conditional logic or testing arrays.
	* Cons: May not be suitable for simple iteration tasks like this benchmark.
4. **`for..of`**:
	* Pros: Modern and concise; easy to read and maintain; no need to worry about indices.
	* Cons: Limited support in older browsers; may require additional setup.

**Library and Special JS Features**

None of the provided test cases use external libraries or special JavaScript features. The focus is solely on comparing the performance of these four loop approaches.

**Other Considerations**

When choosing a loop approach, consider the following factors:

* **Readability**: How easy is the code to understand?
* **Performance**: Will this choice impact your application's speed or efficiency?
* **Maintainability**: Can you easily modify or extend this code later?

**Alternative Loop Approaches**

Some alternative loop approaches not included in this benchmark are:

* **`while` loops**: These use a conditional statement to iterate over the array.
* **`for-in` loops**: These iterate over the properties of an object, but can be applied to arrays with some modifications.
* **Generators and iterators**: These allow for more functional programming styles and can be useful in certain scenarios.

Keep in mind that each loop approach has its strengths and weaknesses. Choose the one that best fits your specific use case and performance requirements.

Related benchmarks:

Do something with for vs foreach vs some vs for..of (version: 0)

Compare loop performance

Comparing performance of: for vs foreach vs some vs for..of

Created: 3 years ago by: Guest

Jump to the latest result

for

foreach

some

for..of

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):