Benchmark: `Array.prototype.concat` vs `spread operator`

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 ]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat
spread operator

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Windows

View result in a separate tab

Test name	Executions per second
Array.prototype.concat	10370293.0 Ops/sec
spread operator	37807480.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Name:** `Array.prototype.concat` vs `spread operator`

**Description:** The benchmark compares the performance of two approaches for merging arrays: the traditional `concat()` method and the new ES6 spread operator (`...`).

**Options Compared:**

1. **Traditional `concat()` method**: This is a built-in array method that takes another array as an argument and returns a new array containing all elements from both arrays.
2. **Spread Operator (`...`)**: Introduced in ES6, this operator allows you to expand an array by its elements into a new array.

**Pros and Cons of Each Approach:**

1. **Traditional `concat()` method:**
	* Pros:
		+ Wide support across older browsers
		+ Easy to read and understand for developers familiar with the method
	* Cons:
		+ Creates a new array, which can lead to performance issues when dealing with large datasets
		+ Can be slower compared to spread operator due to the overhead of function calls
2. **Spread Operator (`...`):**
	* Pros:
		+ More concise and expressive than traditional `concat()`
		+ Creates a new array, but in a more efficient way (no function call)
		+ Generally faster performance compared to traditional `concat()`
	* Cons:
		+ Requires support for ES6+ syntax
		+ May not be as readable for developers unfamiliar with the spread operator

**Other Considerations:**

* The benchmark also considers the use of a specific JavaScript library, but since there is no mention of one being used, we can assume it's a native JavaScript implementation.
* There are no special JS features or syntaxes mentioned in this benchmark.

**Alternatives:**

If you need to compare other array merging approaches, some alternatives include:

1. Using `Array.prototype.reduce()`: This method allows you to iterate over the elements of an array and accumulate them into a new array.
2. Using `Array.prototype.push()`: This method allows you to add one or more elements to the end of an array.
3. Using a custom implementation using loops: For example, using a nested loop structure to iterate over the elements of both arrays.

Keep in mind that these alternatives may have different performance characteristics and trade-offs compared to the spread operator and traditional `concat()` method.

Related benchmarks:

`Array.prototype.concat` vs `spread operator` (version: 0)

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

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

Created: one year ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

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):