Benchmark: for vs new Array.fill

Script Preparation code:

var x=0;

Tests:

for
for( let i=1000; i; i-- ){ x++; }
reduce
x = new Array(1000).fill(0).reduce((x)=>x++)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
reduce

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36 Edg/115.0.1901.203

Browser/OS: Chrome 115 on Linux

View result in a separate tab

Test name	Executions per second
for	12573.6 Ops/sec
reduce	688715.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Overview**

MeasureThat.net allows users to create and run JavaScript microbenchmarks, comparing different approaches to achieve a specific goal. In this case, we have two benchmark definitions: `for` and `reduce`.

**Benchmark Definition JSON**

The provided JSON represents a benchmark definition for the `for vs new Array.fill` test.

* `"Name"`: The name of the benchmark.
* `"Description"`: A brief description of the benchmark (in this case, null).
* `"Script Preparation Code"`: JavaScript code that is executed before running each test case. In this case, it initializes a variable `x` to 0.
* `"Html Preparation Code"`: HTML code that is executed before running each test case (in this case, null).

**Individual Test Cases**

We have two individual test cases:

1. `"for"`
	* `"Benchmark Definition"`: The JavaScript code used in the benchmark. This time loop increments `x` from 1000 down to 1.
2. `"reduce"`
	* `"Benchmark Definition"`: A one-liner that creates a new array of length 1000 filled with zeros, then uses the `reduce()` method to increment `x`.

**Library Usage**

In the `"reduce"` benchmark definition, we see the usage of the built-in JavaScript library `Array.prototype.reduce()`. This function applies a reduction operation on an array, typically used for cumulative calculations.

The purpose of `Array.prototype.reduce()` is to apply a callback function to each element in an array, accumulating a result. In this case, it's used to increment `x` by 1 for each iteration.

**Special JS Feature/Syntax**

In the `"reduce"` benchmark definition, we see the usage of a higher-order function (an anonymous function passed as an argument). This is not uncommon in JavaScript, and it's a powerful feature that allows for concise code.

**Other Alternatives**

For the `for` loop, one alternative could be using `while` loops. Here's an example:
```javascript
var x = 0;
while (x < 1000) {
  x++;
}
```
However, in modern JavaScript, `for` loops are generally preferred over `while` loops due to their readability and maintainability.

For the `"reduce"` benchmark definition, another alternative could be using a simple loop with an incrementing variable:
```javascript
var x = 0;
new Array(1000).forEach(() => {
  x++;
});
```
However, this approach is less readable than using `Array.prototype.reduce()`, and it doesn't have the same level of conciseness as the original benchmark definition.

**Pros and Cons**

Here are some pros and cons for each approach:

* `for` loop:
	+ Pros: Readable, maintainable, and efficient.
	+ Cons: Can be verbose if used with complex loops or nested logic.
* `reduce()` method:
	+ Pros: Concise, readable, and efficient.
	+ Cons: May require more time to understand for beginners, as it's a higher-order function.
* `while` loop:
	+ Pros: Simple, readable, and maintainable.
	+ Cons: Can be less concise than `for` or `reduce()` loops.

In conclusion, the choice of approach depends on personal preference, readability requirements, and performance considerations. MeasureThat.net provides a useful platform for comparing different JavaScript approaches, allowing developers to choose the best solution for their specific use cases.

Related benchmarks:

for vs new Array.fill (version: 0)

Comparing performance of: for vs reduce

Created: 2 years ago by: Guest

Jump to the latest result

for

reduce

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):