Benchmark: Array concat vs spread operator benchmark

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: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.prototype.concat	16134448.0 Ops/sec
spread operator	55145056.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is tested?**

The provided JSON represents a benchmark test case on MeasureThat.net, which compares two approaches to concatenate arrays: the traditional `Array.prototype.concat()` method and the new ES6 spread operator (`...`).

**Options compared**

Two options are being compared:

1. **Traditional `Array.prototype.concat()` method**: This is an older method of concatenating arrays, which creates a new array by combining the elements of two or more existing arrays.
2. **ES6 spread operator (`...`)**: This is a newer feature in JavaScript that allows you to create a new array by spreading the elements of an existing array.

**Pros and cons of each approach**

**Traditional `Array.prototype.concat()` method:**

Pros:

* Widely supported across older browsers
* Easy to understand and implement

Cons:

* Creates a new array, which can lead to performance issues for large datasets
* Can be slower than the spread operator due to the overhead of creating a new array

**ES6 spread operator (`...`):**

Pros:

* More efficient than `concat()`, as it avoids the overhead of creating a new array
* Creates a new array with a more concise syntax

Cons:

* Not supported in older browsers (before Chrome 44, Edge 16)
* Can lead to performance issues if not optimized properly

**Library usage**

In this benchmark, no libraries are used. The script and HTML preparation codes are minimal, indicating that the focus is on comparing the two array concatenation approaches.

**Special JS feature or syntax**

The spread operator (`...`) is a special JavaScript feature introduced in ES6 (2015). It allows you to create a new array by spreading the elements of an existing array. This feature has become increasingly important in modern web development, especially with the rise of ES6 and newer browsers.

**Other alternatives**

For large-scale data processing or performance-critical code, other approaches might be considered:

1. **Array.prototype.slice() + Array.prototype.push()`**: This approach uses `slice()` to create a shallow copy of the original array and then pushes all elements from another array onto the copied array.
2. **Typed Arrays (e.g., Int32Array, Uint8Array)**: For specific data types and performance requirements, using typed arrays might be more efficient than concatenating arrays.

In summary, this benchmark test case is designed to compare two approaches to concatenate arrays in JavaScript: traditional `Array.prototype.concat()` method and the new ES6 spread operator (`...`). The choice of approach depends on the specific use case, browser support, and performance requirements.

Related benchmarks:

Array concat vs spread operator benchmark (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):