Benchmark: Array.from vs Object.assign (2)

Tests:

Array.from
var fooSet = new Set(); for(var i=0;i<10000;i++) { fooSet.add(i); } var other = Array.from(fooSet);
Object.assign
var fooSet = new Set(); for(var i=0;i<10000;i++) { fooSet.add(i); } var other = Object.assign([],fooSet);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.from
Object.assign

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Definition JSON**

The benchmark definition specifies two test cases:

1. `Array.from vs Object.assign (2)`
	* This test compares the performance of two approaches to convert an array-like object to a true array:
		+ `Array.from()`
		+ `Object.assign()`
2. The first test case has a specific benchmark definition, which creates a Set and adds 10,000 elements to it using `for` loop, then converts the Set to an Array using `Array.from()`.
3. The second test case has another specific benchmark definition, which creates a Set and adds 10,000 elements to it using `for` loop, then converts the Set to an Array using `Object.assign()`.

**What are being compared?**

The test compares the performance of two approaches:

1. `Array.from()`: This method creates a new array by copying elements from another iterable (in this case, the Set). It's a concise way to create arrays.
2. `Object.assign()`: This method copies properties from one or more sources (in this case, the Set) and returns an object with those properties.

**Pros and Cons**

Here are some pros and cons of each approach:

1. **Array.from()**
	* Pros:
		+ Concise syntax
		+ Creates a new array without modifying the original iterable
		+ Can handle various types of iterables (e.g., Sets, Maps)
	* Cons:
		+ May incur additional overhead due to its concise syntax and iterator usage
		+ Not as efficient as `Object.assign()` in some cases
2. **Object.assign()**
	* Pros:
		+ Fast and efficient for simple assignments
		+ Can handle complex objects with nested properties
	* Cons:
		+ May not work correctly when dealing with Set-like iterables or Maps
		+ Requires more code to achieve the same result as `Array.from()` (e.g., using `[]` as the target array)

**Other Considerations**

In this specific benchmark, both approaches have similar performance characteristics. However, there are scenarios where one approach might be preferred over the other:

* When working with large datasets or complex iterables, `Array.from()` might provide better performance and readability.
* In situations where you need to modify the original iterable (e.g., using `map()`, `filter()`), `Object.assign()` might be a better choice.

**Library and Special JS Feature**

In this benchmark, there is no specific library being used. However, JavaScript provides various built-in features that can simplify tasks like array conversions:

* `Array.from()`: uses the spread operator (`...`) to create an iterator from an iterable.
* `Object.assign()` does not rely on any special libraries or syntax beyond its built-in implementation.

**Alternatives**

For similar benchmarks, you might also consider testing other approaches for array conversions, such as:

1. Using a `for` loop directly with the desired type (e.g., using a `for...of` loop to create an array)
2. Utilizing third-party libraries or functions like Lodash's `from` function
3. Comparing performance with different JavaScript versions or engines

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.96 Safari/537.36

Browser/OS: Chrome 88 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.from	2374.6 Ops/sec
Object.assign	2633.1 Ops/sec

Related benchmarks:

Array.from vs Object.assign (2) (version: 0)

Comparing performance of: Array.from vs Object.assign

Created: 5 years ago by: Guest

Jump to the latest result

Array.from

Object.assign

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):