Benchmark: Shallow Copy Array

Script Preparation code:

var newArr = ['1', '2', '3', '4'];

Tests:

Slice
const arrCopy = newArr.slice()
Spread
const arrCopy = [...newArr]
Array.from
const arrCopy = Array.from(newArr)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Slice
Spread
Array.from

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided benchmark measures the performance of creating shallow copies of an array in JavaScript using three different methods: `slice()`, spread operator (`...`), and `Array.from()`.

**Methods Compared**

1. **Slice()**: This method creates a new array by slicing the original array from index 0 to the end.
2. **Spread Operator (`...`)**: This method creates a new array by spreading the elements of the original array into a new array.
3. **Array.from()**: This method creates a new array from an iterable (in this case, the original array).

**Pros and Cons**

1. **Slice()**:
	* Pros: Simple and efficient, as it only requires a single function call.
	* Cons: May not be suitable for large arrays due to memory allocation overhead.
2. **Spread Operator (`...`)**:
	* Pros: Can create shallow copies of larger arrays without the need for explicit loops or array methods.
	* Cons: Requires JavaScript version 13+ (or later) and may have performance implications due to the creation of a new array object.
3. **Array.from()**:
	* Pros: Can create shallow copies of larger arrays with a single function call, similar to the spread operator.
	* Cons: May not be as efficient as `slice()` for very large arrays.

**Library Usage**

None of the provided methods use any external libraries.

**Special JavaScript Features/Syntax**

The test cases use the following special JavaScript features/syntax:

* **Spread Operator (`...`)**: This feature is only available in JavaScript version 13+ (or later).
* None other syntax are used.

**Other Alternatives**

If you need to create shallow copies of arrays in JavaScript, there are two alternative methods:

1. **Loops**: You can use a simple loop to create a new array and copy the elements from the original array.
2. **Array.prototype.map()**: This method returns a new array with the same number of elements as the original array, where each element is copied from the corresponding element in the original array.

Example:
```javascript
const arrCopy = [];
for (let i = 0; i < newArr.length; i++) {
    arrCopy.push(newArr[i]);
}
```
or
```javascript
const arrCopy = newArr.map((element) => {
    // You can add additional logic here if needed
    return element;
});
```

Keep in mind that these alternatives may not be as efficient or concise as the methods used in the benchmark, but they can be useful in certain situations.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36

Browser/OS: Chrome 116 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Slice	21226136.0 Ops/sec
Spread	25811414.0 Ops/sec
Array.from	10139793.0 Ops/sec

Related benchmarks:

Shallow Copy Array (version: 0)

Comparing performance of: Slice vs Spread vs Array.from

Created: one year ago by: Guest

Jump to the latest result

Slice

Spread

Array.from

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):