Benchmark: Nj9ZJ^FuK4AJ#wKE

Script Preparation code:

var length = 100000;

function* range(from, to, step = 1) {
    if (!step) return;
    if (!to) to = from, from = 0;

    if (from < to && step > 0) {
        while (from < to) {
            yield from;
            from += step;
        }
    } else if (from > to && step < 0) {
        while (from > to) {
            yield from;
            from += step;
        }
    }
}

function* range_undefined(from, to, step = 1) {
    if (!step) return;
    if (!to) to = from, from = 0;

    if (from < to && step > 0) {
        while (from < to) {
            yield;
            from += step;
        }
    } else if (from > to && step < 0) {
        while (from > to) {
            yield;
            from += step;
        }
    }
}

Tests:

fori
for (let i = 0; i < length; i++) {}
lazy range with index number
for (const i of range(length)) {}
range with index number
for (const i of Array.from(Array(length).keys())) {}
range without index number
for (const i of Array.from(Array(length))) {}
lazy range without index number
for (const i of range_undefined(length)) {}

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
fori
lazy range with index number
range with index number
range without index number
lazy range without index number

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.93 Safari/537.36

Browser/OS: Chrome 96 on Windows

View result in a separate tab

Test name	Executions per second
fori	106.6 Ops/sec
lazy range with index number	533.8 Ops/sec
range with index number	362.4 Ops/sec
range without index number	1583.6 Ops/sec
lazy range without index number	507.7 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided JSON represents a benchmark test created on MeasureThat.net, which compares the performance of different loop iteration approaches in JavaScript. The benchmark tests four variants:

1. **For loop with index variable**: `for (let i = 0; i < length; i++) {}`
2. **Lazy range with index number**: `for (const i of range(length)) {}`
3. **Range with index number using `Array.from()`**: `for (const i of Array.from(Array(length).keys())) {}`
4. **Range without index number**: `for (const i of range_undefined(length)) {}`

**Comparison Options**

The benchmark compares the performance of these four variants:

* **For loop with index variable**: uses a traditional for loop with an index variable to iterate over the range.
* **Lazy range with index number**: uses the `range` function to create an iterator, which yields values on demand. This approach avoids creating an array or modifying the original data.
* **Range with index number using `Array.from()`**: creates an array of indices using `Array.from(Array(length).keys())`, and then iterates over this array using a for loop.
* **Range without index number**: uses the `range_undefined` function to create an iterator that yields values without creating an array or modifying the original data.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **For loop with index variable**:
	* Pros: easy to understand, widely supported.
	* Cons: can be slower due to the overhead of indexing.
2. **Lazy range with index number**:
	* Pros: avoids array creation, efficient use of memory.
	* Cons: may not be as intuitive for some developers.
3. **Range with index number using `Array.from()`**:
	* Pros: easy to implement, works well with existing codebases.
	* Cons: creates an additional array, which can consume memory.
4. **Range without index number**:
	* Pros: avoids array creation and indexing overhead.
	* Cons: may require more complex iterator implementation.

**Library and Special JS Features**

The benchmark uses the following libraries and special JS features:

* None explicitly mentioned in the provided JSON.

However, it's worth noting that some modern browsers (like Chrome) have built-in support for iterators (such as `for...of` loops with generators) through the ECMAScript 2015 standard.

**Other Alternatives**

If you're looking for alternative approaches to loop iteration, consider the following:

* **Fibers**: a concurrency model that allows for efficient and lightweight execution of tasks.
* **Web Workers**: a way to run JavaScript in parallel, using separate threads for computation.
* **Reactive programming libraries**: like RxJS or React Query, which provide a more functional programming style for handling asynchronous data.

Keep in mind that each alternative has its own strengths and weaknesses, and the choice ultimately depends on your specific use case and performance requirements.

Related benchmarks:

Nj9ZJ^FuK4AJ#wKE (version: 0)

Compare loop performance

Comparing performance of: fori vs lazy range with index number vs range with index number vs range without index number vs lazy range without index number

Created: 3 years ago by: Guest

Jump to the latest result

fori

lazy range with index number

range with index number

range without index number

lazy range without index number

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):