Benchmark: Array concat vs spread operator vs push (forEach) x

Tests:

Array.prototype.concat
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].concat(params);
spread operator
var params = [ "hello", true, 7 ] var other = [ 1, 2, ...params ]
Push
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ]; params.forEach((item) => { other.push(item); });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat
spread operator
Push

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided benchmark and explain what's being tested, compared, and the pros/cons of each approach.

**Benchmark Overview**

The benchmark compares the performance of three methods for concatenating or appending elements to an array:

1. `Array.prototype.concat()`
2. The new ES6 spread operator (`...`)
3. The `push()` method with a callback function using `forEach()`.

**Test Case 1: Array.prototype.concat**

In this test case, the code concatenates two arrays using the traditional `concat()` method:
```javascript
var params = [ "hello", true, 7 ];
var other = [ 1, 2 ].concat(params);
```
The purpose of this test is to measure the performance of the `concat()` method.

Pros:

* Widely supported and well-established method.
* Simple and easy to understand.

Cons:

* Can be slower than other methods due to the overhead of creating a new array.

**Test Case 2: Spread Operator**

In this test case, the code uses the spread operator (`...`) to concatenate two arrays:
```javascript
var params = [ "hello", true, 7 ];
var other = [ 1, 2, ...params ];
```
The purpose of this test is to measure the performance of the new ES6 spread operator.

Pros:

* Fast and efficient.
* Concise and easy to read.

Cons:

* Requires a modern browser that supports the spread operator (e.g., Firefox 98+).
* May not work in older browsers or environments.

**Test Case 3: Push with forEach**

In this test case, the code uses the `push()` method with a callback function using `forEach()` to append elements to an array:
```javascript
var params = [ "hello", true, 7 ];
var other = [ 1, 2 ];
params.forEach((item) => {
  other.push(item);
});
```
The purpose of this test is to measure the performance of the `push()` method with a callback function.

Pros:

* Fast and efficient.
* Can work in older browsers or environments that don't support the spread operator.

Cons:

* Requires the use of `forEach()` which can be slower than other methods due to the overhead of iterating over the array.
* More verbose and complex code compared to the spread operator.

**Library: null**

There are no libraries used in this benchmark.

**Special JS Feature/Syntax: ES6 Spread Operator**

The ES6 spread operator (`...`) is a new feature introduced in ECMAScript 2015. It allows for concise array creation by spreading elements of an array into a new array.

**Alternatives**

If you need to compare the performance of these methods, here are some alternative approaches:

* Use a different array data structure, such as `Array.from()` or `Set`.
* Compare the performance of these methods on different types of data, such as large arrays or objects.
* Test the performance of other concatenation methods, such as using `reduce()` or `map()`.
* Use a benchmarking framework that provides more features and flexibility, such as Jest or Benchmark.js.

Related benchmarks:

Array concat vs spread operator vs push (forEach) x (version: 0)

Compare the new ES6 spread operator with the traditional concat() method and push

Comparing performance of: Array.prototype.concat vs spread operator vs Push

Created: 4 years ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

Push

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):