Benchmark: Array.from vs Spread vs For

Tests:

Array.from
var fooMap = new Map(); for(var i=0;i<1000;i++) { fooMap.set(i, i); } var other = Array.from(fooMap);
Spread
var fooMap = new Map(); for(var i=0;i<1000;i++) { fooMap.set(i, i); } var other = [...fooMap];
For
var fooMap = new Map(); for(var i=0;i<1000;i++) { fooMap.set(i, i); } var other = []; for(var i=0;i<fooMap.size;i++) { other.push(fooMap.get(i)); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.from
Spread
For

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; rv:109.0) Gecko/20100101 Firefox/113.0

Browser/OS: Firefox 113 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
Array.from	13922.2 Ops/sec
Spread	13859.3 Ops/sec
For	17869.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON data and explain what's being tested, compared, and the pros/cons of each approach.

**Benchmark Definition**

The benchmark is defined as three test cases: `Array.from`, `Spread`, and `For`. These test cases aim to compare the performance of different ways to convert a JavaScript `Map` object into an array.

**Test Cases**

1. **Array.from**
	* The first test case converts a `Map` object with 1000 key-value pairs to an array using the `Array.from()` method.
	* Purpose: To demonstrate how `Array.from()` can be used to convert a `Map` object into an array.
2. **Spread**
	* The second test case converts a `Map` object with 1000 key-value pairs to an array by spreading its values directly using the `...` operator.
	* Purpose: To demonstrate how spreading an array-like object can be used to convert it into an array.
3. **For**
	* The third test case converts a `Map` object with 1000 key-value pairs to an array by iterating over its size and pushing each value into a new array using a `for` loop.
	* Purpose: To demonstrate how manual iteration can be used to convert a `Map` object into an array.

**Libraries and Special JS Features**

None of the test cases use any external libraries. However, they do utilize JavaScript's built-in features:

* `Map`: A JavaScript object that stores key-value pairs.
* `Array.from()`: A method that creates a new array from an iterable or an array-like object.
* Spreading operator (`...`): Allows for converting an array-like object into an array.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **Array.from()**
	* Pros:
		+ Efficient and concise way to convert `Map` objects to arrays.
		+ Supports various iteration options (e.g., `Promise.all`, `async/await`).
	* Cons:
		+ May not be as intuitive for beginners, as it requires knowledge of the method's signature.
2. **Spread**
	* Pros:
		+ Simple and elegant way to convert array-like objects into arrays.
		+ Works well with modern JavaScript versions (ECMAScript 2018+).
	* Cons:
		+ May not be as efficient for large datasets, as it creates a new array and copies the values.
3. **For**
	* Pros:
		+ Suitable for older JavaScript versions or environments without support for `Array.from()` or spreading operators.
		+ Allows for manual control over iteration and array construction.
	* Cons:
		+ More verbose and error-prone compared to `Array.from()` or spreading operators.

**Other Alternatives**

If you need an alternative approach, consider the following:

1. `Object.values()`: Converts a map object into an array by getting its values using the `Object.values()` method.
2. `Array.prototype.concat()`: Combines multiple arrays into one using the `concat()` method.
3. `reduce()`: Utilizes the `reduce()` method to create an array from a sequence of values.

Keep in mind that these alternatives might have varying levels of performance and convenience depending on your specific use case.

Related benchmarks:

Array.from vs Spread vs For (version: 0)

Comparing performance of: Array.from vs Spread vs For

Created: one year ago by: Guest

Jump to the latest result

Array.from

Spread

For

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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