Benchmark: Array.concat vs Array.push vs Array.push spread

Tests:

push
const params = [ "hello", true, 7 ]; const a = [1,2]; a.push.apply(a, params);
concat
var params = [ "hello", true, 7 ]; const a = [1,2]; var other = a.concat(params);
spread
var params = [ "hello", true, 7 ]; const a = [1,2]; var other = a.push(...params);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
push
concat
spread

Fastest: N/A

Slowest: N/A

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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.

**Benchmark Definition**

The benchmark is defined by three test cases, each testing a different approach to adding elements to an array:

1. `Array.concat vs Array.push vs Array.push spread`

This suggests that the benchmark is comparing the performance of using the `concat()` method versus the `push()` method with and without the spread operator (`...`) to add elements to an existing array.

**Options Compared**

The options being compared are:

* `concat()`: A method that creates a new array by copying all elements from one or more source arrays.
* `push()`: A method that adds one or more elements to the end of an array and returns the new length of the array.
* `push spread` (or `...`): A syntax feature introduced in ECMAScript 2015 (ES6) that allows adding multiple elements to an array using a spread operator.

**Pros and Cons**

Here are some pros and cons of each approach:

* `concat()`: Pros:
	+ Can be used with arrays of different lengths.
	+ Returns the original array unchanged.
	Cons:
	+ Creates a new array, which can be memory-intensive for large datasets.
	+ May incur overhead due to array creation and copying.
* `push()`: Pros:
	+ Modifies the original array in-place.
	+ Can be faster than `concat()` since it doesn't create a new array.
Cons:
	+ Requires multiple function calls (e.g., `a.push(1)`, `a.push(2)`), which can lead to overhead due to function call overhead.
	+ May not be as efficient for large arrays since it requires updating the length of the array.
* `push spread` (`...`): Pros:
	+ Simplifies the code and eliminates the need for multiple function calls.
	+ Can be faster than `concat()` since it doesn't require creating a new array.

**Library**

There is no library being used in this benchmark. The test cases rely solely on built-in JavaScript methods and syntax features.

**Special JS Feature or Syntax**

The spread operator (`...`) is a special feature introduced in ECMAScript 2015 (ES6). It allows adding multiple elements to an array using a single expression, eliminating the need for `push()` with multiple arguments. This feature provides a concise and expressive way to add elements to arrays.

**Other Considerations**

When choosing between these approaches, consider the following factors:

* Performance: If you're working with large datasets or performance-critical code, `push spread` might be the fastest option.
* Code readability: If you need to write concise code that's easy to read and maintain, `push spread` is a good choice.
* In-place modification: If you want to modify an array in-place without creating a new one, `push()` is a better option.

**Alternatives**

Other alternatives for adding elements to an array include:

* Using `Array.prototype.reduce()`: A method that applies a reduction function to all elements of the array and returns a single value.
* Using `Array.prototype.forEach()`: A method that executes a callback function once for each element in the array without modifying the array.
* Using `Set` or `Map` data structures: If you're working with unique elements or need to iterate over an array, these data structures can provide better performance and efficiency.

Related benchmarks:

Array.concat vs Array.push vs Array.push spread (version: 0)

Comparing performance of: push vs concat vs spread

Created: 5 years ago by: Guest

Jump to the latest result

push

concat

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):