Benchmark: for vs foreach vs some vs for..of (ES6)

Script Preparation code:

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

Tests:

for
for (let i = 0; i < array.length; i++) { if (array[i] !== undefined) {} }
foreach
array.forEach(i => { if (array[i] !== undefined) {} });
some
array.some(i => { if (array[i] !== undefined) {} });
for..of
for (const i of array) { if (array[i] !== undefined) {} }

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:

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.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark test case created on MeasureThat.net. The benchmark aims to compare the performance of four different loop constructs: traditional `for` loops, `forEach`, `some`, and the newer `for...of` syntax (introduced in ES6).

**Loop Constructs Comparison**

1. **Traditional `for` Loops**: This is the most common type of loop in JavaScript. It uses an explicit counter variable to iterate over the array.
```javascript
for (let i = 0; i < array.length; i++) {
    if (array[i] !== undefined) {}
}
```
Pros:

* Well-known and widely supported syntax.

Cons:

* Can be error-prone, especially when dealing with edge cases or large arrays.

2. **`forEach`**: This method is part of the Array prototype and executes a callback function once for each element in the array.
```javascript
array.forEach(i => {
    if (array[i] !== undefined) {}
});
```
Pros:

* Convenient and easy to use, especially when working with modern JavaScript engines.

Cons:

* May incur additional overhead due to method call and closure creation.

3. **`some`**: This method returns `true` as soon as the callback function returns `true` for at least one element in the array.
```javascript
array.some(i => {
    if (array[i] !== undefined) {}
});
```
Pros:

* Can be useful when dealing with arrays that have only a few elements.

Cons:

* May not be the best choice for large arrays, as it stops iterating as soon as it finds a true condition.

4. **`for...of`**: This newer syntax is designed to iterate over iterable objects, such as arrays.
```javascript
for (const i of array) {
    if (array[i] !== undefined) {}
}
```
Pros:

* More concise and expressive than traditional `for` loops.

Cons:

* Less widely supported than traditional `for` loops in older JavaScript engines.

**Library Used**

None mentioned in the provided JSON. However, it's worth noting that some benchmarks may use libraries like BenchmarkJS or Microbenchmark to measure performance.

**Special JS Features/Syntax**

None explicitly mentioned in the provided JSON. However, it's essential to note that ES6 introduced several new features and syntax improvements, such as `let`, `const`, arrow functions, and template literals, which are not included in this benchmark.

**Other Alternatives**

Alternative loop constructs, like `while` loops or recursive functions, are not included in this benchmark. However, they can be used to compare performance with the provided options.

Keep in mind that benchmarking results may vary depending on the JavaScript engine, browser, and device being tested. MeasureThat.net provides a consistent and controlled environment for comparing different loop constructs, ensuring accurate and reliable results.

Related benchmarks:

for vs foreach vs some vs for..of (ES6) (version: 0)

Compare loop performance

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

Created: 4 years ago by: Guest

Jump to the latest result

for

foreach

some

for..of

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):