Benchmark: Array concat vs spread operator vs push___

Tests:

Array.prototype.concat
const params = [ ...Array(100).keys() ]; const other = params.concat(100);
spread operator
const params = [ ...Array(100).keys() ] const other = [...params,100 ]
Push
const params = [ ...Array(100).keys() ]; params.push(100);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat
spread operator
Push

Fastest: N/A

Slowest: N/A

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

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

**Benchmark Definition**

The benchmark is designed to compare the performance of three different approaches for concatenating an array:

1. **Push**: Using the `push()` method to add elements to the end of the array.
2. **Spread Operator**: Using the new ES6 spread operator (`...`) to create a copy of the original array and then add elements to it.
3. **Array.prototype.concat()**: Using the `concat()` method from the Array prototype to concatenate two arrays.

**Options Compared**

The benchmark is comparing the performance of these three approaches:

* **Push**: The `push()` method modifies the original array and returns `undefined`.
* **Spread Operator**: Creates a new array by spreading the original array, then adds more elements to it.
* **Array.prototype.concat()**: Returns a new array that contains all the elements from both arrays.

**Pros and Cons of Each Approach**

1. **Push**:
	* Pros: Simple, efficient, and doesn't create an extra object in memory.
	* Cons: Modifies the original array, can be slower for large arrays due to the need to update the length property.
2. **Spread Operator**:
	* Pros: Creates a new array, easy to read and understand, and avoids modifying the original array.
	* Cons: Can create an extra object in memory if not used carefully (e.g., `const arr = [...arr, 1];` instead of `arr.push(1)`).
3. **Array.prototype.concat()**:
	* Pros: Creates a new array, efficient, and avoids modifying the original array.
	* Cons: Requires an additional method call (`concat()`), which can be slower than using `push()` directly.

**Library Usage**

There is no explicit library usage in this benchmark. However, it's worth noting that `Array.prototype.concat()` relies on the Array prototype, which is a built-in part of JavaScript.

**Special JS Feature or Syntax**

The spread operator (`...`) was introduced in ES6 and allows for creating new arrays by spreading existing arrays. This syntax is not specific to any particular browser or version but has become widely supported.

**Other Alternatives**

Other alternatives for concatenating arrays include:

* Using `Array.prototype.push()` multiple times: `arr.push(1); arr.push(2);`
* Using `Array.prototype splice()`: `arr.splice(arr.length, 0, 1); arr.splice(arr.length, 0, 2);`
* Using a loop to create a new array: `const newArr = []; for (let i = 0; i < arr.length; i++) { newArr.push(i); }`

However, the spread operator and `Array.prototype.concat()` are generally considered more efficient and readable than these alternatives.

Related benchmarks:

Array concat vs spread operator vs push___ (version: 0)

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

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

Created: 6 years ago by: Guest

Jump to the latest result

Array.prototype.concat

spread operator

Push

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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