Benchmark: Concat vs Spread risnik

Tests:

Concat
const arr1 = [ "hello", true, 7 ]; const arr2 = [1, 2, 3, 4, 5]; const result = arr1.concat(arr2);
Spread
const arr1 = [ "hello", true, 7 ]; const arr2 = [1, 2, 3, 4, 5]; const result = [...arr1, ...arr2];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Concat
Spread

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

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

**What is being tested?**

The benchmark measures the performance difference between two approaches: concatenation using the `concat()` method and spreading using the spread operator (`...`). The test cases are identical, with the only difference being how the arrays are combined.

**Options compared:**

There are two options being compared:

1. **Concatenation**: Using the `concat()` method to combine two arrays.
```javascript
const result = arr1.concat(arr2);
```
Pros:

* Wide browser support (most browsers have implemented `concat()` since ancient times)
* Simple and readable syntax

Cons:

* May be slower than spreading, especially for large arrays
* Can lead to memory allocations if not properly optimized

2. **Spreading**: Using the spread operator (`...`) to combine two arrays.
```javascript
const result = [...arr1, ...arr2];
```
Pros:

* Often faster than concatenation, especially for large arrays
* More efficient memory usage since it avoids creating a new array object

Cons:

* May not work in older browsers (only supported since ECMAScript 2015)
* Less readable syntax for some developers

**Library usage:**

There is no explicit library being used in the benchmark. However, it's worth noting that the spread operator is a part of the JavaScript standard library.

**Special JS feature or syntax:**

The use of the spread operator (`...`) is an example of ECMAScript 2015 (ES6) syntax, which was introduced to make array manipulation more concise and expressive.

**Other alternatives:**

If you want to avoid using the spread operator, you can also use other methods like `Array.prototype.push()` or `Array.prototype.unshift()`, but these may not be as efficient or readable.

Here's an example of using `Array.prototype.push()`:
```javascript
const result = [];
result.push(...arr1);
result.push(...arr2);
```
And here's an example of using `Array.prototype.unshift()`:
```javascript
const result = [...arr1, ...arr2];
```
However, these alternatives may not be as efficient or readable as spreading.

**Benchmark preparation code:**

The provided benchmark preparation code is empty, which means that the test cases are already pre-prepared and ready to run. The script only contains the test cases with identical input arrays (`arr1` and `arr2`).

Related benchmarks:

Concat vs Spread risnik (version: 0)

Comparing performance of: Concat vs Spread

Created: 3 years ago by: Guest

Jump to the latest result

Concat

Spread

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):