Benchmark: While vs For loop

Tests:

For loop
var acts = "BRA|BRA|FLR|VSL|BRA".split("|"); for (var i = 0; i < acts.length -1; i++) { if (acts[i] == "BRA") acts.splice(i, 1); }
While loop
var acts = "BRA|BRA|FLR|VSL|BRA".split("|"); var i = acts.length; while (i--) { if (acts[i] == "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

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 14 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:149.0) Gecko/20100101 Firefox/149.0

Browser/OS: Firefox 149 on Windows

View result in a separate tab

Test name	Executions per second
For loop	2795576.2 Ops/sec
While loop	2062276.8 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll explain the benchmark in detail.

**Benchmark Overview**

The benchmark compares the performance of two loops: For Loop and While Loop, specifically when removing elements from an array using `splice()` method. The goal is to determine which loop approach is faster on Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0.

**Options Compared**

The benchmark compares two approaches:

1. **For Loop**: A traditional for loop uses an incrementing index to iterate over the array elements.
```javascript
for (var i = 0; i < acts.length -1; i++) {
  if (acts[i] == "BRA") acts.splice(i, 1);
}
```
2. **While Loop**: A while loop continues to execute as long as a condition is true. In this case, the loop iterates over the array elements using a decrementing index.
```javascript
var i = acts.length;
while (i--) {
  if (acts[i] == "BRA") acts.splice(i, 1);
}
```
**Pros and Cons**

* **For Loop**:
	+ Pros: Can be more intuitive for developers familiar with traditional loops.
	+ Cons: May lead to off-by-one errors or indexing issues due to the incrementing index.
* **While Loop**:
	+ Pros: Allows for more flexibility in controlling the loop iteration, such as decrementing the index.
	+ Cons: Can be less intuitive for developers not familiar with while loops.

**Library and Special JS Features**

The benchmark uses no specific libraries or special JavaScript features. However, it's worth noting that `splice()` method modifies the original array, which can lead to unexpected behavior in certain scenarios.

**Other Alternatives**

If you want to explore alternative loop approaches, consider:

1. **Iterators**: Use iterators (e.g., `for...of`) instead of traditional loops.
2. **Array.prototype.forEach()**: Utilize the built-in `forEach()` method for a more modern and efficient way to iterate over arrays.

In conclusion, this benchmark provides a simple yet informative comparison between two common loop approaches in JavaScript: For Loop and While Loop. By understanding the trade-offs and pros and cons of each approach, developers can make informed decisions when writing their own code.

Related benchmarks:

While vs For loop (version: 0)

Comparing performance of: For loop vs While loop

Created: 9 years ago by: Guest

Jump to the latest result

For loop

While loop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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