Benchmark: 12132132132131243214124

Tests:

from
let n = 10000, length = 50; const result = []; for (let i = 0; i < n; ++i) { result.push(Array.from({length}, _ => length)); }
fill
let n = 10000, length = 50; const result = []; for (let i = 0; i < n; ++i) { result.push(Array(length).fill(length)); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
from
fill

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36

Browser/OS: Chrome 128 on Linux

View result in a separate tab

Test name	Executions per second
from	38.2 Ops/sec
fill	415.3 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark is designed to compare two approaches for creating arrays of repeated values: using `Array.from()` with a callback function (`_ => length`) versus using `Array(length).fill(length)`.

**Approaches Compared**

1. **`Array.from()` with a callback function**: This approach uses the `Array.from()` method, which takes an array-like object and converts it into a new array. The callback function `_ => length` is applied to each element of the resulting array, effectively repeating the value `length`.
2. **`Array(length).fill(length)`**: This approach creates a new array with `length` elements and then fills each element with the value `length`.

**Pros and Cons of Each Approach**

1. **`Array.from()` with a callback function**:
	* Pros: More concise, readable code.
	* Cons: May be slower due to the overhead of creating a callback function.
2. **`Array(length).fill(length)`**:
	* Pros: Faster, as it creates an array and fills it in a single operation.
	* Cons: Less readable code.

**Other Considerations**

* The `from` method is part of the ECMAScript standard, so it's supported by most modern browsers. However, some older browsers might not support it.
* The `fill()` method is also widely supported, but its behavior can vary depending on the browser and version.

**Library Used**

None in this case, as both approaches use built-in JavaScript methods.

**Special JS Features or Syntax**

The benchmark uses a syntax feature common to modern JavaScript: template literals (`\r\n`). However, it's worth noting that older browsers might not support this feature or might interpret it differently.

**Benchmark Preparation Code and Test Cases**

The benchmark preparation code is empty, as the script itself contains all the necessary logic. The test cases are defined in the `Individual test cases` section, which describes two separate scenarios:

1. **"from"`**: This test case uses the `Array.from()` method with a callback function.
2. **"fill"`**: This test case uses the `Array(length).fill(length)` approach.

**Alternatives**

If you wanted to run this benchmark in a different environment, you could consider using:

* A JavaScript engine like V8 or SpiderMonkey (which powers Firefox)
* A testing framework like Jest or Mocha
* A benchmarking library like Benchmark.js

Keep in mind that the specific implementation details might vary depending on your chosen platform and tools.

Related benchmarks:

12132132132131243214124 (version: 0)

Comparing performance of: from vs fill

Created: 3 months ago by: Guest

Jump to the latest result

from

fill

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):