Benchmark: Set union methods

HTML Preparation code:

<script src="https://cdnjs.cloudflare.com/ajax/libs/nanoid/4.0.1/index.browser.js" integrity="sha512-YFaQHp+hWX9CMeIMngYK23kSIWaYlgsswmzmIdEw/HcK/5NLhXY2MbT0wQB5DnUzjW1uky4quIHtksukqZGkMw==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>

Script Preparation code:

const SET_SIZE = 1000;

var set1 = new Set()
var set2 = new Set()
while (i < SET_SIZE) {
    const nid = 'key:'+Math.random();
    set1.add(nid);
    if (i % 2 == 0) set2.add(nid);
    i++;
}
while (i < SET_SIZE / 2) {
    set2.add('key:'+Math.random());
}

Tests:

Spreading
const set3 = new Set([...set1, ...set2]); console.log(set3.size)
Set.forEach + Set.add
const set3 = new Set(set1); set2.forEach(el => set3.add(el)); console.log(set3.size)
Generators
const set3 = new Set(function*() { yield* set1; yield* set2; }()); console.log(set3.size)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Spreading
Set.forEach + Set.add
Generators

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 5 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36

Browser/OS: Chrome 144 on Mac OS X 10.15.7

View result in a separate tab

Spreading

717K/s

Set.forEach + Set.add

709K/s

Generators

605K/s

View exact numbers

Test name	Executions per second
✓ Spreading	717,428 Ops/sec
Set.forEach + Set.add	709,121 Ops/sec
Generators	604,515 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 analyzed.

**Benchmark Overview**

The benchmark is designed to compare different methods for unionizing JavaScript Sets. A Set in JavaScript is an unordered collection of unique values. The benchmark aims to determine which method is most efficient for combining two Sets.

**Test Cases**

There are three test cases:

1. **Spreading**: This method uses the spread operator (`...`) to create a new Set from the elements of `set1` and `set2`.
```javascript
const set3 = new Set([...set1, ...set2]);
console.log(set3.size);
```
Pros: Simple and concise. This method is widely supported across modern browsers.

Cons: May not be as efficient as other methods for very large Sets due to the creation of a new array.

2. **Set.forEach + Set.add**: This method iterates over `set1` using `forEach` and adds each element to `set3` using `add`.
```javascript
const set3 = new Set(set1);
set2.forEach(el => set3.add(el));
console.log(set3.size);
```
Pros: Can be more efficient for large Sets because it avoids creating a temporary array.

Cons: May have higher overhead due to the iteration and function calls.

3. **Generators**: This method uses a generator function to yield elements from `set1` and `set2`, which are then added to `set3`.
```javascript
const set3 = new Set(function*() { yield* set1; yield* set2; }());
console.log(set3.size);
```
Pros: Can be more efficient for very large Sets because it avoids creating temporary arrays.

Cons: May have higher overhead due to the creation of a generator function and its associated computations.

**Library Used**

The benchmark uses the `nanoid` library, which generates random IDs. However, this library is not explicitly used in the test cases; instead, it's used for the browser's identification string (`RawUAString`) in the benchmark results.

**Special JavaScript Features or Syntax**

None of the methods use any special JavaScript features or syntax that would affect their performance.

**Alternatives**

Other alternatives for unionizing Sets include:

* Using the `Set.prototype.union()` method (not supported in older browsers).
* Using a library like `lodash.set` or `underscore.util.union`.
* Implementing a custom union function using bitwise operations or other techniques.

Keep in mind that the choice of method depends on the specific use case, performance requirements, and compatibility considerations.

Set union methods (version: 0)

Different ways to union JS Sets

Comparing performance of: `Spreading vs Set.forEach + Set.add vs Generators`

Created: 2 years ago by: Guest

Go to the latest result

Spreading

Set.forEach + Set.add

Generators

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Set union methods (version: 0)

Different ways to union JS Sets

Comparing performance of: Spreading vs Set.forEach + Set.add vs Generators

Created: 2 years ago by: Guest

Go to the latest result

Spreading

Set.forEach + Set.add

Generators

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `Spreading vs Set.forEach + Set.add vs Generators`