Benchmark: Array.prototype.slice vs spread operator fixed 2

Tests:

Array.prototype.slice
var params = [ "hello", true, 7 ]; var other = params.slice();
spread operator
var params = [ "hello", true, 7 ] var other = [ ...params ]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.slice
spread operator

Fastest: N/A

Slowest: N/A

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.prototype.slice	56079604.0 Ops/sec
spread operator	69673360.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and its test cases.

**Benchmark Purpose**

The purpose of this benchmark is to compare the performance of two approaches for creating a copy of an array: the traditional `Array.prototype.slice()` method and the new ES6 spread operator (`[ ...params ]`).

**Options Compared**

There are two options being compared:

1. **Traditional `Array.prototype.slice()`:** This method creates a shallow copy of an array by returning a new array with references to the original elements.
2. **New ES6 Spread Operator (`[ ...params ]`):** This operator creates a new array by iterating over the elements of the original array and creating a new element for each one.

**Pros and Cons**

* **Traditional `Array.prototype.slice()`:**
	+ Pros:
		- Simple and widely supported.
		- Can be used in older browsers that don't support the spread operator.
	+ Cons:
		- Creates a shallow copy, which may not be suitable for all use cases (e.g., when dealing with objects).
		- May have performance overhead due to the creation of a new array object.
* **New ES6 Spread Operator (`[ ...params ]`):**
	+ Pros:
		- More concise and expressive than traditional `slice()`.
		- Creates a deep copy by default, which can be beneficial in some scenarios.
		- Faster performance since it avoids creating an intermediate array object.
	+ Cons:
		- May not be supported in older browsers or environments that don't have ES6 enabled.
		- Can lead to unexpected behavior if not used carefully (e.g., when dealing with arrays of objects).

**Library and Special JS Features**

There are no libraries being tested, but the benchmark does use the new ES6 spread operator (`[ ...params ]`), which is a feature introduced in modern JavaScript.

**Other Considerations**

When choosing between these two approaches, consider the specific requirements of your project. If you need to work with arrays of objects and want to ensure that any nested objects are copied recursively, the spread operator might be a better choice. However, if you're targeting older browsers or require more control over the creation of array copies, traditional `Array.prototype.slice()` might be a safer option.

**Alternatives**

Other alternatives for creating array copies include:

1. **`Array.prototype.concat()`:** This method creates a new array by concatenating multiple arrays.
2. **`Object.assign()`:** This method creates a new object by copying properties from an existing object or array.
3. **`Array.from()`:** This method creates a new array from an iterable (e.g., an array expression).

Each of these alternatives has its own trade-offs and use cases, and the choice ultimately depends on the specific requirements of your project.

I hope this explanation helps! Let me know if you have any further questions.

Related benchmarks:

Array.prototype.slice vs spread operator fixed 2 (version: 0)

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

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

Created: 5 years ago by: Guest

Jump to the latest result

Array.prototype.slice

spread operator

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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