Benchmark: Array.prototype.concat vs spread operator number 2

Tests:

Array.prototype.concat
var params = [ "hello", true, 7 ]; var old = [1,2]; var other = [...old, ...params];
spread operator
var params = [ "hello", true, 7 ]; var old = [1,2]; var other = old.concat(params);

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Test case name	Result
Array.prototype.concat
spread operator

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Slowest: N/A

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Autogenerated LLM Summary (model gemma2:9b, generated one year ago):

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This benchmark compares the performance of two methods for combining arrays in JavaScript:

**1. `Array.prototype.concat()`:** This is the traditional method, which creates a new array by appending all elements from one or more existing arrays.

```javascript
var params = ["hello", true, 7];
var old = [1,2];
var other = old.concat(params); 
```

**2. The Spread Operator (`...`):** This is a newer feature introduced in ES6 (ECMAScript 2015). It allows you to expand the elements of an array into individual items.

```javascript
var params = ["hello", true, 7];
var old = [1,2];
var other = [...old, ...params];
```

**Pros and Cons:**

* **Spread Operator:** Generally considered more concise and readable due to its simple syntax. It can also be used in a wider range of contexts beyond array concatenation, such as passing multiple arguments to functions or creating new arrays with selected elements.

* **Potential Con:**  Might have slightly higher overhead compared to `concat` depending on the size and complexity of the arrays involved.
* **`Array.prototype.concat()`:**  Well-established method with predictable behavior. Can be more efficient for very large arrays, as it often optimizes memory usage.

* **Potential Con:** Less readable syntax, especially when concatenating multiple arrays.

**Alternatives:**

* **`Array.from()`:** Another ES6 feature that can be used to create new arrays. It's particularly useful when you need to transform existing iterables (like strings or NodeLists) into arrays.
* **Manual Looping:**  For simple cases, you could manually loop through the arrays and build a new array. However, this is generally less efficient than using built-in methods like `concat` or the spread operator.

**Considerations:**

The best approach depends on your specific use case:

* **Readability and Conciseness:** If your primary concern is code readability and conciseness, the spread operator is usually preferred.
* **Performance:** For very large arrays or performance-critical applications, `Array.prototype.concat()` might offer a slight performance advantage.  However, the difference is often negligible in practice.

Let me know if you have any other benchmarks you'd like me to analyze!

Related benchmarks:

Array.prototype.concat vs spread operator number 2 (version: 0)

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

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

Created: 6 years ago by: Guest

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Array.prototype.concat

spread operator

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model gemma2:9b, generated one year ago):