Benchmark: for vs do while 2

Script Preparation code:

var newBody = document.createElement("div");


for (let i; i < 1000; i++) {
	var divAdded = document.createElement("div");
	divAdded.classList.add("ggclass");
	newBody.appendChild(divAdded);
}

Tests:

//1.case For i
var case1 = document.getElementsByClassName("ggclass"); for (var i = 0; i < case1.length; i++) { // 반복할 내용 console.log(case1[i]); }
2 do while
var case1 = document.getElementsByClassName("ggclass"); do { console.log(case1[i]); i++ } while (i < case1.length);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
//1.case For i
2 do while

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; rv:135.0) Gecko/20100101 Firefox/135.0

Browser/OS: Firefox 135 on Linux

View result in a separate tab

Test name	Executions per second
//1.case For i	4789710.5 Ops/sec
2 do while	157628.9 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided benchmark tests the performance difference between two loops: a traditional `for` loop and a `do-while` loop, both used to iterate over an array of HTML elements (`case1`) that contain the class "ggclass".

**Loop Options Compared**

The benchmark compares two approaches:

1. **Traditional For Loop**: The code uses a `for` loop with a variable `i`, initialized before the loop, and increments after each iteration.
```javascript
for (let i; i < 1000; i++) {
    // ...
}
```
Pros:

* Easy to understand and write for developers familiar with traditional loops.
* Can be optimized using techniques like loop unrolling or caching.

Cons:

* May have slower execution due to the overhead of initializing variables before each iteration.

2. **Do-While Loop**: The code uses a `do-while` loop that executes the body only once, and then checks the condition before the next iteration.
```javascript
do {
    console.log(case1[i]);
    i++;
} while (i < case1.length);
```
Pros:

* Can be faster since it doesn't require initializing variables on each iteration.

Cons:

* May have slower performance due to the need for a conditional check after each execution, which can lead to branch prediction errors in some cases.

**Library Usage**

The benchmark uses the `document` object and its methods to access the HTML elements. Specifically, it uses `getElementsByClassName()` to retrieve an array of elements with the class "ggclass".

Pros:

* Provides a convenient way to access DOM elements in JavaScript.
* Allows for easy modification of the DOM structure.

Cons:

* May have slower performance due to the overhead of accessing the DOM.
* Can be sensitive to changes in the DOM structure or layout.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in this benchmark. The code is written in standard ECMAScript.

**Alternative Approaches**

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

1. **Using `Array.prototype.forEach()`**: Instead of using a loop, you can use the `forEach` method to iterate over an array.
```javascript
case1.forEach(element => console.log(element));
```
This approach is often faster and more readable than traditional loops.

2. **Using `Array.prototype.map()`**: If you want to perform some operation on each element of the array, you can use the `map` method.
```javascript
const results = case1.map(element => console.log(element));
```
This approach is often faster and more concise than using a loop or `forEach`.

3. **Using a microbenchmarking library**: If you want to create a more comprehensive benchmark, you can consider using a dedicated microbenchmarking library like Benchmark.js or Microbenchmark.

Keep in mind that the choice of approach depends on your specific use case, performance requirements, and personal preference.

Related benchmarks:

for vs do while 2 (version: 1)

Comparing performance of: //1.case For i vs 2 do while

Created: 2 years ago by: Registered User

Jump to the latest result

//1.case For i

2 do while

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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