Benchmark: Push up - for vs foreach vs some vs for..of

Script Preparation code:

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

Tests:

for
result = [] const aLen = array.length for (var i = 0; i < aLen; i++) { result.push(array[i]); }
foreach
result = [] array.forEach(function(i) { result.push(array[i]); });
some
result = [] array.some(function(i) { result.push(array[i]); });
for..of
result = [] for (const 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 (Macintosh; Intel Mac OS X 10.15; rv:88.0) Gecko/20100101 Firefox/88.0

Browser/OS: Firefox 88 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
for	530011.8 Ops/sec
foreach	7446906.0 Ops/sec
some	7568922.0 Ops/sec
for..of	251295.5 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided benchmark, "Push up - for vs foreach vs some vs for..of", tests the performance of different loop methods in JavaScript: `for`, `forEach`, `some`, and `for..of`. The goal is to determine which method provides the best performance.

**Loop Options Compared**

The four loop options are compared:

1. **`for`**: An old-school, traditional loop that uses a variable to iterate over an array.
2. **`forEach`**: A modern loop that uses the `Array.prototype.forEach()` method, which iterates over an array and executes a callback function for each element.
3. **`some`**: A loop that uses the `Array.prototype.some()` method, which returns `true` if at least one element in the array passes the test implemented by the provided function.
4. **`for..of`**: A modern loop that uses the `for...of` loop syntax, which iterates over an array and executes a block of code for each element.

**Pros and Cons**

1. **`for`**:
	* Pros: Simple, familiar to most developers.
	* Cons: Can be slower than other methods due to its explicit indexing.
2. **`forEach`**:
	* Pros: Easy to read and maintain, no need to worry about indices.
	* Cons: May have performance issues if the callback function is complex or creates side effects.
3. **`some`**:
	* Pros: Can stop iterating as soon as a condition is met, which can be beneficial for large arrays.
	* Cons: Returns `true` as soon as a condition is met, which might not be desirable in all cases.
4. **`for..of`**:
	* Pros: Modern, concise syntax; no need to worry about indices or callback functions.
	* Cons: May require additional setup if the loop needs to iterate over multiple arrays.

**Library and Special JS Features**

None of the individual test cases use any libraries other than the built-in `Array` prototype methods. However, the `for...of` loop syntax is a modern JavaScript feature that was introduced in ECMAScript 2015 (ES6).

**Other Alternatives**

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

1. **While loops**: Another traditional loop method that uses a condition to control iteration.
2. **For-in loops**: A loop that iterates over the properties of an object, which can be useful when working with objects instead of arrays.

However, these alternatives are not included in the provided benchmark.

**Benchmark Preparation Code**

The preparation code for each test case is as follows:

1. Create a new array with 100 elements.
2. Initialize an empty array `result`.
3. For each loop option, push elements from the input array to the `result` array using the corresponding loop method.

The actual benchmarking code will vary depending on the loop method being tested and the browser/ device configuration.

Related benchmarks:

Push up - for vs foreach vs some vs for..of (version: 2)

Compare loop performance

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

Created: 3 years ago by: Registered User

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):