Benchmark: Array.prototype.concat vs spread operator bugfixed

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js'></script>

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 ]
jQuery merge
var params = [ "hello", true, 7 ]; var other = $.merge([1, 2], params);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat
spread operator
jQuery merge

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided benchmark, `Array.prototype.concat vs spread operator bugfixed`, is designed to compare the performance of two approaches for merging arrays in JavaScript: the traditional `concat()` method and the new ES6 spread operator (`...`).

**Options Compared**

Two options are compared:

1. **`Array.prototype.concat`**: The traditional way of concatenating arrays using the `concat()` method.
2. **Spread Operator (`...`)**: A new way of spreading elements from an array into another array using the `...` syntax.

**Pros and Cons of Each Approach**

**`Array.prototype.concat`**:

Pros:

* Wide support across different browsers and versions
* Familiar and well-established API

Cons:

* Can lead to performance issues for large arrays due to the creation of a new array object
* May not be optimized for certain use cases, such as when the source array is modified after concatenation

**Spread Operator (`...`)**:

Pros:

* More concise and expressive syntax compared to `concat()`
* Optimized for performance by using a single operation instead of creating a new array object
* Supports efficient iteration over the spread elements

Cons:

* May not be supported in older browsers or versions that do not implement ES6 features
* Can lead to unexpected behavior if not used correctly (e.g., when dealing with non-iterable values)

**Other Considerations**

When choosing between these two approaches, it's essential to consider the specific requirements of your use case. If you need a concise and expressive way to merge arrays without performance concerns, the spread operator is likely the better choice. However, if you're working in an environment where `concat()` is more suitable (e.g., due to older browser support), using that method might be more practical.

**Library Used**

In this benchmark, jQuery's `$` object is used as a library for the `.merge()` method. The jQuery merge function is not part of the standard JavaScript API and provides an alternative way to concatenate arrays.

**Special JS Feature or Syntax**

There are no special features or syntaxes mentioned in this benchmark.

**Alternative Approaches**

Some alternative approaches for merging arrays include:

1. **Using `Array.prototype.slice()`**: This method can be used to create a shallow copy of an array, which can then be concatenated with another array using the spread operator.
```javascript
var params = [ "hello", true, 7 ];
var other = [...params.slice(), 1, 2];
```
2. **Using `Array.prototype.reduce()`**: This method can be used to concatenate arrays by accumulating elements from an initial array and adding more elements iteratively.
```javascript
var params = [ "hello", true, 7 ];
var other = [1, 2].reduce((acc, val) => [...acc, ...val], []);
```
3. **Using a custom implementation**: Depending on the specific requirements of your use case, you might consider implementing your own array merge function.

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

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36

Browser/OS: Chrome 68 on Linux

View result in a separate tab

Test name	Executions per second
Array.prototype.concat	5394321.0 Ops/sec
spread operator	15259345.0 Ops/sec
jQuery merge	2608538.0 Ops/sec

Related benchmarks:

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

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

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

Created: 6 years ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

jQuery merge

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):