Benchmark: Spread vs concat vs forEach array v1000

Tests:

Concat
const arr1 = Array.from({ length: 1000000}).map((_, i) => i); const arr2 = Array.from({ length: 1000000}).map((_, i) => i); const arr3 = Array.from({ length: 1000000}).map((_, i) => i); const finallArr1 = arr1.concat(arr2).concat(arr3);
forEach
const arr1 = Array.from({ length: 1000000}).map((_, i) => i); const arr2 = Array.from({ length: 1000000}).map((_, i) => i); const arr3 = Array.from({ length: 1000000}).map((_, i) => i); const finalArr2 = []; arr1.forEach((e) => finalArr2.push(e)); arr2.forEach((e) => finalArr2.push(e)); arr3.forEach((e) => finalArr2.push(e));
Spread
const arr1 = Array.from({ length: 1000000}).map((_, i) => i); const arr2 = Array.from({ length: 1000000}).map((_, i) => i); const arr3 = Array.from({ length: 1000000}).map((_, i) => i); const finalArr3 = [...arr1, ...arr2, ...arr3];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Concat
forEach
Spread

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.

Let's break down the provided benchmark and explain what's being tested.

The benchmark is comparing three different approaches to concatenate (join) or manipulate arrays in JavaScript:

1. **Spread Operator (`...`)**: This syntax was introduced in ECMAScript 2015 and allows you to expand an array into individual elements, which can then be used as arguments to a function or concatenated with other arrays.
2. **Array Concatenation (`concat()` method)**: This is the traditional way of concatenating two or more arrays in JavaScript.
3. **`forEach()` loop**: This is a method that allows you to iterate over an array, performing some action on each element.

**Pros and Cons:**

* **Spread Operator (`...`)**
	+ Pros:
		- More concise and expressive than traditional concatenation methods.
		- Can be used to expand arrays into individual elements for use in functions or as arguments.
	+ Cons:
		- Not all browsers support the spread operator (e.g., older versions of Internet Explorer).
		- Can lead to confusion if not properly understood.
* **Array Concatenation (`concat()` method)**
	+ Pros:
		- Widely supported across different browsers and JavaScript engines.
		- Easy to understand and implement.
	+ Cons:
		- Less concise than the spread operator.
		- Can be slower due to the overhead of creating new arrays.
* **`forEach()` loop**
	+ Pros:
		- Allows for more control over iteration and can be used with other methods like `map()`.
	+ Cons:
		- Requires explicit loops, which can lead to boilerplate code.

**Library Usage:**

None of the benchmark tests explicitly use any libraries or external dependencies. The arrays are created using built-in JavaScript functions (`Array.from()`).

**Special JS Features/Syntax:**

The spread operator is the only special feature/syntax being tested in this benchmark. However, it's worth noting that other features like `let` and `const` declarations (used for variable declaration) were introduced later than the spread operator.

**Alternative Approaches:**

There are alternative ways to concatenate or manipulate arrays in JavaScript, such as using `Array.prototype.push()` with a loop or using libraries like Lodash. However, these approaches are not being tested in this specific benchmark.

Some other alternatives that could be explored include:

* Using `Array.reduce()` for concatenation
* Using `Array.prototype.slice()` and `Array.prototype.splice()` to manipulate arrays
* Using third-party libraries like Lodash for array manipulation

Overall, the current benchmark is designed to test the performance of three different approaches to array concatenation and manipulation in JavaScript.

Related benchmarks:

Spread vs concat vs forEach array v1000 (version: 0)

Comparing performance of: Concat vs forEach vs Spread

Created: 3 years ago by: Guest

Jump to the latest result

Concat

forEach

Spread

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):