Benchmark: Array filling - MeasureThat.net

Tests:

map
Array(9).fill(null).map(() => Array(3).fill(null))
literal
Array(9).fill([null, null, null])

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map
literal

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36

Browser/OS: Chrome 72 on Mac OS X 10.14.3

View result in a separate tab

Test name	Executions per second
map	384578.7 Ops/sec
literal	3743604.8 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 provided benchmark and explain what's being tested.

**What is being tested?**

The benchmark measures the performance of JavaScript arrays in two different scenarios:

1. **Literal**: Filling an array with literal values (`[null, null, null]`) using the `fill()` method.
2. **Map**: Creating a nested array structure by filling one array with another array that contains three elements filled with `null` values using the `map()` method.

**Options compared**

In this benchmark, two main options are being compared:

* Literal: Using the `fill()` method to set an array of literal values.
* Map: Using the `map()` method to create a nested array structure.

**Pros and Cons of each approach**

1. **Literal (using fill())**
	* Pros:
		+ Simple and straightforward way to set an array of values.
		+ Can be faster since it's a built-in function that doesn't require dynamic typing.
	* Cons:
		+ May not be as flexible or expressive as other methods, such as `map()` or destructuring assignment.
2. **Map (using map())**
	* Pros:
		+ More flexible and expressive than literal values, allowing for complex transformations.
		+ Can be faster since it's a built-in function that doesn't require explicit looping.
	* Cons:
		+ May have overhead due to the need to create an intermediate array.

**Library usage**

The `Array(9).fill(null)` syntax is using the `Array` constructor with the `fill()` method, which is not specifically a library. However, some JavaScript implementations may use libraries or extensions that optimize this specific syntax for performance. In this benchmark, it's likely that the `fill()` method is being used directly in the browser's engine.

**Special JS feature or syntax**

The `map()` function and the spread operator (`...`) are not explicitly mentioned as special features or syntaxes in the provided explanation. However, they are essential concepts in JavaScript that enable functional programming styles and array transformations.

**Other alternatives**

To achieve similar results to these two approaches:

1. Using a loop: `Array(9).fill(null); var result = []; for (var i = 0; i < 3; i++) { result.push(Array(3).fill(null)); }`
2. Destructuring assignment: `const result = Array(9).map(() => Array(3).fill(null));`

**Benchmark preparation code**

The provided script preparation code is empty, which means that the test cases are being executed directly in the benchmark environment.

Overall, this benchmark provides a simple and concise way to compare the performance of two different approaches: literal values using `fill()` and nested array structures using `map()`. It's an excellent example of how to write effective microbenchmarks for JavaScript.

Related benchmarks:

Array filling (version: 0)

Comparing performance of: map vs literal

Created: 5 years ago by: Registered User

Jump to the latest result

map

literal

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):