Benchmark: copy array: slice vs Object.assign

Tests:

splice
var array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; var output = array.slice();
Object.assign
var array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; var output = Object.assign([], array);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
splice
Object.assign

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's dive into the world of MeasureThat.net and explore what's tested in this benchmark.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmarking test case. The `Benchmark Definition` section defines the basic setup for the test, including:

* A script preparation code block (`var array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];`) that creates an array of numbers.
* An HTML preparation code block (empty in this case) that isn't relevant to the JavaScript performance test.

**Individual Test Cases**

The benchmark consists of two individual test cases:

1. **splice**: This test case uses the `slice()` method to create a copy of the original array.
2. **Object.assign**: This test case uses the `Object.assign()` method to create a shallow copy of the original array.

**What's being compared?**

In this benchmark, two approaches are being compared:

* `splice()`: A method that creates a new array by copying elements from the original array and returns the new array.
* `Object.assign()`: A method that takes an existing object and copies all enumerable own properties from one or more source objects into a new target object.

**Pros and Cons of each approach**

1. **splice()**:
	* Pros: Can be used to create a copy of an array, and it's often faster than `Object.assign()` for small arrays.
	* Cons: It creates a new array in memory, which can lead to increased memory usage and garbage collection overhead.
2. **Object.assign()**:
	* Pros: Creates a shallow copy of the original array, which can be more efficient than creating a new array with `splice()`. Also, it's often faster for large arrays.
	* Cons: It can create unnecessary objects in memory, leading to increased garbage collection overhead.

**Library and purpose**

There is no explicit library mentioned in this benchmark. However, `Object.assign()` uses the W3C standard method for assigning properties from one or more source objects to a target object.

**Special JS feature or syntax**

None are explicitly mentioned in this benchmark.

**Other alternatives**

For creating an array copy, other approaches could be:

* `Array.prototype.slice.call()`: Similar to `splice()`, but creates a new array using the `slice()` method on an existing array.
* `Array.from()`: Creates a new array from an iterable source, such as another array or an array-like object.

**Conclusion**

In this benchmark, two approaches are compared: `splice()` and `Object.assign()`. The choice between these methods depends on the specific requirements of your use case. If you need to create a shallow copy of a small array for faster execution, `Object.assign()` might be the better choice. However, if memory usage is not a concern, and you want to avoid creating unnecessary objects, `splice()` could be a better option.

Keep in mind that this benchmark only tests these two approaches on arrays. Other types of data structures or use cases might require different methods for performance optimization.

Related benchmarks:

copy array: slice vs Object.assign (version: 0)

Comparing performance of: splice vs Object.assign

Created: 3 years ago by: Guest

Jump to the latest result

splice

Object.assign

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):