Benchmark: While vs For loop vs Map

Script Preparation code:

var acts = "BRA|BRA|FLR|VSL|BRA".split("|");

Tests:

For loop
for (var i = 0; i < acts.length -1; i++) { if (acts[i] == "BRA") acts.splice(i, 1); }
While loop
var i = acts.length; while (i--) { if (acts[i] == "BRA") acts.splice(i, 1); }
Map loop
acts.map((act,i)=>{ if (act == "BRA") acts.splice(i, 1); })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
For loop
While loop
Map loop

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36 Edg/125.0.0.0

Browser/OS: Chrome 125 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
For loop	4804802.5 Ops/sec
While loop	9228352.0 Ops/sec
Map loop	20004164.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring the performance of different JavaScript loops can be an interesting and instructive exercise.

**Benchmark Overview**

The provided benchmark is designed to measure the performance of three different types of loops: For loop, While loop, and Map loop. The script generates an array `acts` with a specific pattern (BRA|BRA|FLR|VSL|BRA) and then uses each loop type to remove the first occurrence of "BRA" from the array.

**Options Compared**

The benchmark compares three different approaches:

1. **For loop**: Uses a traditional for loop to iterate over the indices of the `acts` array.
2. **While loop**: Uses a while loop to decrement the index variable until it reaches the end of the array.
3. **Map loop**: Uses the Array.prototype.map() method to create a new array with the modified elements, effectively removing the first occurrence of "BRA" from each element.

**Pros and Cons**

* **For loop**: Easy to understand and implement, but can be slower due to the overhead of index calculations.
* **While loop**: Can be faster than for loops because it avoids the overhead of incrementing an index variable. However, it requires manual management of the loop condition.
* **Map loop**: Often the fastest option, as it uses a more efficient algorithm and avoids the need for manual iteration.

**Library Usage**

The benchmark uses the Array.prototype.map() method, which is a built-in JavaScript function that applies a given function to each element in an array. The purpose of this library is to provide a concise and expressive way to create new arrays with modified elements.

**Special JS Features/Syntax**

None mentioned explicitly, but it's worth noting that the use of the spread operator (`...`) in the script preparation code is a modern JavaScript feature introduced in ECMAScript 2015 (ES6). However, it's unlikely to have a significant impact on performance compared to other factors like loop optimization and browser differences.

**Other Alternatives**

If you want to explore alternative approaches, here are some options:

* **Reduce**: Instead of using map() or a for/while loop, you can use the Array.prototype.reduce() method to achieve the same result.
* **Filter**: You can also use the Array.prototype.filter() method to create a new array with filtered elements.
* **Native functions**: Depending on the browser and JavaScript version, native functions like `Array.prototype.forEach()` or `Array.prototype.every()` might be suitable alternatives.

For a more detailed analysis of the performance differences between these approaches, I recommend exploring the MeasuringThat.net website, which provides a wealth of information on JavaScript benchmarking.

Related benchmarks:

While vs For loop vs Map (version: 0)

Comparing performance of: For loop vs While loop vs Map loop

Created: one year ago by: Registered User

Jump to the latest result

For loop

While loop

Map loop

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):