Benchmark: Array.prototype.concat vs spread operator 12

Tests:

Array.prototype.concat
[ 1, 2 ].concat([ "hello", true, 7 ]);
spread operator
[ ...[ 1, 2 ], ...[ "hello", true, 7 ] ]

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: 2 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36

Browser/OS: Chrome 112 on Linux

View result in a separate tab

Test name	Executions per second
Array.prototype.concat	6794179.5 Ops/sec
spread operator	20755648.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark compares two ways to concatenate arrays in JavaScript: `Array.prototype.concat` (traditional method) and the spread operator (`...`).

**Options Compared**

The options being compared are:

1. **Traditional Method**: Using `Array.prototype.concat()` to concatenate two arrays.
2. **Spread Operator**: Using the spread operator (`...`) to concatenate two arrays.

**Pros and Cons of Each Approach**

* **Traditional Method (concat())**:
	+ Pros: Well-established, widely supported, and easy to understand for many developers.
	+ Cons: Can be slower than the spread operator in modern JavaScript engines.
* **Spread Operator (...)**:
	+ Pros: Fast, concise, and efficient. It's a part of the modern JavaScript standard (ES6+).
	+ Cons: May require additional knowledge or attention from developers to write correctly.

**Library Usage**

In this benchmark, no specific libraries are used beyond the built-in `Array` prototype and the JavaScript language itself.

**Special JS Features/Syntax**

The spread operator (`...`) is a relatively new feature introduced in ECMAScript 2015 (ES6). It allows for more concise array concatenation by spreading elements into a new array. This feature was widely adopted after its introduction, making it a part of modern JavaScript development workflows.

**Other Considerations**

This benchmark focuses on the performance difference between two common methods of array concatenation in JavaScript. By comparing these options, the goal is to provide insight into which method is faster and more efficient for developers writing JavaScript code.

**Alternatives**

Other alternatives for array concatenation might include:

1. Using `Array.prototype.push()` with multiple arguments.
2. Using the `reduce()` method or other functional programming techniques to concatenate arrays.
3. Employing third-party libraries or polyfills that offer optimized array concatenation methods.

These alternatives may have different performance characteristics, code readability trade-offs, and developer familiarity factors compared to the traditional concat() and spread operator approaches tested in this benchmark.

Related benchmarks:

Array.prototype.concat vs spread operator 12 (version: 0)

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

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

Created: 2 years ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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