Benchmark: Array.prototype.slice() vs Array.prototype.slice(0)

Tests:

Array.prototype.slice()
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].slice();
Array.prototype.slice(0)
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].slice(0);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.slice()
Array.prototype.slice(0)

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36

Browser/OS: Chrome 97 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.prototype.slice()	162511456.0 Ops/sec
Array.prototype.slice(0)	171695136.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the benchmark.

**What is being tested?**

The provided JSON represents two test cases that compare the performance of `Array.prototype.slice()` with and without an optional first argument (`slice(0)`).

**Options compared:**

There are two options being compared:

1. `Array.prototype.slice()`: This method returns a shallow copy of a portion of an array, starting from the beginning (index 0) to the specified index.
2. `Array.prototype.slice(startIndex)`: This is an optional parameter that allows you to specify a starting index for the slice operation.

**Pros and Cons:**

* Without `slice(0)` (`Array.prototype.slice()`), the method returns a shallow copy of a portion of an array, but it does not guarantee that the resulting array will have exactly `n` elements (where `n` is the length of the original array). This can lead to unexpected behavior if you're relying on the length of the resulting array being equal to the specified index.
* With `slice(0)` (`Array.prototype.slice(0)`), the method returns a shallow copy of an empty portion of the array, which is guaranteed to have exactly 0 elements. This ensures consistency and predictability.

In terms of performance, using `slice(0)` can be beneficial when you know the original array's length and want to create an exact subset with the same length as specified by the starting index. On the other hand, omitting the starting index (i.e., using `Array.prototype.slice()`) allows for more flexibility but may introduce some overhead due to the lack of guaranteed results.

**Other considerations:**

* Both methods are optimized for performance and use similar underlying algorithms.
* The absence of `slice(0)` can lead to more computations when you're relying on the resulting array's length being equal to the specified index. This might be a consideration in certain scenarios, especially if you need predictable results.

**Library usage:**

There is no explicit library mentioned in the provided JSON. However, `Array.prototype.slice()` is an intrinsic method of the JavaScript Array prototype, so it doesn't rely on any external libraries.

**Special JS feature or syntax:**

The provided benchmark uses modern JavaScript features, specifically:

* The use of template literals (`var params = [ "hello", true, 7 ];`) and array literals ([1, 2]).
* The `slice()` method with an optional starting index (`slice(0)`).

These features are widely supported across most modern browsers and environments.

**Other alternatives:**

If you're looking for alternative approaches to slice operations, consider using other methods like:

* `Array.prototype.slice.call(array)`: Creates a new array from the elements of another array.
* `array.subarray(startIndex, endIndex)`: Returns a shallow copy of a portion of an array, starting from the specified index and ending at the end of the array (exclusive).
* `slice() from other libraries or modules**: There are several alternative library implementations available that provide optimized slice operations, such as Lodash's `_.slice()` function.

Keep in mind that these alternatives might introduce additional dependencies or have varying levels of compatibility with different browsers and environments.

Related benchmarks:

Array.prototype.slice() vs Array.prototype.slice(0) (version: 0)

Comparing performance of: Array.prototype.slice() vs Array.prototype.slice(0)

Created: 2 years ago by: Guest

Jump to the latest result

Array.prototype.slice()

Array.prototype.slice(0)

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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