Benchmark: Array `concat` vs `push` vs Spread operator

Tests:

`concat`
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].concat(params);
`push`
var params = [ "hello", true, 7 ]; params.push(1); params.push(2);
Spread operator
var params = [ "hello", true, 7 ] var other = [ 1, 2, ...params ]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
`concat`
`push`
Spread operator

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark compares three different ways to concatenate an array in JavaScript:

1. `concat()`
2. `push()` with multiple elements
3. Spread operator (`...`)

Each test case uses a similar setup: creating an initial array `params` with some values, and then concatenating it with another array using one of the tested methods.

**What is being compared?**

The benchmark compares the execution time, performance, or speed of each method for these three test cases. The goal is to determine which method is the fastest and most efficient in terms of performance.

**Options compared:**

1. `concat()`: This method creates a new array by copying elements from both arrays.
2. `push()` with multiple elements: In this approach, multiple elements are added using the `push()` method, which modifies the original array.
3. Spread operator (`...`): This method uses the spread operator to create a new array by spreading elements from one or more sources.

**Pros and Cons of each approach:**

1. `concat()`:
	* Pros: Creates a new array, which can be useful when working with immutable data structures or when you want to avoid modifying the original array.
	* Cons: Can be slower than other methods due to the overhead of creating a new array.
2. `push()` with multiple elements:
	* Pros: Modifies the original array, which can be efficient for large datasets, and avoids creating a new array.
	* Cons: Requires multiple calls to `push()`, which can be slower than using an operator like `concat()` or spread.
3. Spread operator (`...`):
	* Pros: Creates a new array in a concise way and avoids the need for explicit loops or `push()` calls.
	* Cons: May not be as readable or intuitive for some developers, especially those familiar with traditional array manipulation methods.

**Library usage**

There are no specific libraries used in this benchmark. The focus is on comparing different JavaScript features and syntax.

**Special JS feature or syntax**

The spread operator (`...`) is a relatively recent addition to the JavaScript language, introduced in ECMAScript 2015 (ES6). It allows for more concise array creation and manipulation.

**Benchmark results**

The latest benchmark results show that:

1. `push()` with multiple elements is the fastest approach, followed closely by the spread operator.
2. `concat()` is slower than both of these methods but still relatively fast.

Keep in mind that these results may vary depending on specific use cases, dataset sizes, and JavaScript engine versions.

**Other alternatives**

If you're interested in exploring alternative approaches or optimizing your code further, consider:

1. Using `Array.prototype.concat()`, which creates a new array and avoids modifying the original.
2. Utilizing libraries like Lodash or Ramda for functional programming and array manipulation.
3. Leveraging modern JavaScript features, such as async/await and generators, for more efficient and readable code.

Remember that performance optimization is an ongoing process, and it's essential to consider your specific use case, dataset size, and target audience when choosing the most suitable approach.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36

Browser/OS: Chrome 75 on Mac OS X 10.14.6

View result in a separate tab

Test name	Executions per second
`concat`	2891633.8 Ops/sec
`push`	26510666.0 Ops/sec
Spread operator	23794398.0 Ops/sec

Related benchmarks:

Array `concat` vs `push` vs Spread operator (version: 0)

Comparing performance of: `concat` vs `push` vs Spread operator

Created: 5 years ago by: Guest

Jump to the latest result

`concat`

`push`

Spread operator

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):