Benchmark: Iteration Speed 2

Script Preparation code:

   var arr = [];
   for (var i = 0; i < 50000; i++) {
       arr[i] = i;
   }

Tests:

while loop
let i = 0 while(i < arr.length) { arr[i] i++ }
for loop
for(let i = 0; i < arr.length; i++) { arr[i] }
do .. while loop
let i = 0 do { arr[i] i++ } while(i < arr.length)
forEach loop
arr.forEach((data) => { data })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
while loop
for loop
do .. while loop
forEach loop

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
while loop	28426.3 Ops/sec
for loop	33236.5 Ops/sec
do .. while loop	26654.0 Ops/sec
forEach loop	5206.7 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and the pros and cons of each approach.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmarking test case on MeasureThat.net. The test measures the execution speed of different looping constructs in JavaScript: `while`, `for`, `do-while`, and `forEach`.

**Script Preparation Code**

The script preparation code is the same for all test cases:
```javascript
var arr = [];
for (var i = 0; i < 50000; i++) {
  arr[i] = i;
}
```
This code initializes an array `arr` with 50,000 elements and assigns each element its index value.

**Html Preparation Code**

The html preparation code is empty for all test cases, which means that no HTML-related setup or teardown is performed before running the benchmark.

**Looping Constructs**

Each test case measures a different looping construct:

1. `while` loop:
```javascript
let i = 0;
while (i < arr.length) {
  arr[i];
  i++;
}
```
2. `for` loop:
```javascript
for (let i = 0; i < arr.length; i++) {
  arr[i];
}
```
3. `do-while` loop:
```javascript
let i = 0;
do {
  arr[i];
  i++;
} while (i < arr.length);
```
4. `forEach` loop:
```javascript
arr.forEach((data) => {
  data;
});
```
**Comparison of Looping Constructs**

The pros and cons of each looping construct are as follows:

* `while` loop:
	+ Pros: allows for more flexibility in the loop condition, can be used with arrays or other iterable objects.
	+ Cons: requires manual incrementation of the index variable, can lead to off-by-one errors if not handled carefully.
* `for` loop:
	+ Pros: easier to read and write than `while` loops, allows for more control over the loop iteration.
	+ Cons: less flexible than `while` loops, requires explicit initialization of the loop variables.
* `do-while` loop:
	+ Pros: similar to `while` loops but with an additional check at the end of each iteration.
	+ Cons: can be harder to read and write, may not be as common in modern JavaScript code.
* `forEach` loop:
	+ Pros: concise and readable, allows for easy iteration over arrays or other iterable objects.
	+ Cons: limited control over the loop iteration, may not be suitable for complex logic.

**Library Usage**

None of the test cases use any external libraries or dependencies. The looping constructs are used in isolation to compare their execution speeds.

**Special JS Features/ Syntax**

None of the test cases explicitly use special JavaScript features like async/await, generators, or decorators. However, the `for...of` loop (not shown in this example) is not mentioned either.

**Alternative Approaches**

Other alternatives for implementing looping constructs in JavaScript include:

* Using `Array.prototype.map()`, `Array.prototype.filter()`, and other array methods to achieve similar results.
* Utilizing third-party libraries like Lodash or Ramda for functional programming-related looping constructs.
* Implementing custom looping constructs using recursive functions, iteration over arrays or objects, or using Web Workers.

Keep in mind that this is a simplified example, and real-world benchmarking scenarios may involve additional complexity and nuance.

Related benchmarks:

Iteration Speed 2 (version: 2)

Comparing performance of: while loop vs for loop vs do .. while loop vs forEach loop

Created: 4 years ago by: Registered User

Jump to the latest result

while loop

for loop

do .. while loop

forEach loop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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