Benchmark: Set iterator vs Array.from

Tests:

Iterate
var fooSet = new Set(); for(var i=0;i<100;i++) { fooSet.add(i); } let x = 0; for (const f of fooSet) { x++; }
Spread
var fooSet = new Set(); for(var i=0;i<100;i++) { fooSet.add(i); } let x = 0; for (const item of [...fooSet]){ x++; }

Historical Performance Data aggregated from 8 community runs

Desktop Results:

Chrome 8 runs

Spread

383K/s

Iterate

375K/s

View exact numbers

✓ Spread: 382,669 ops/sec
• Iterate: 375,438 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Iterate
Spread

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/137.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 137 on Android

View result in a separate tab

Iterate

611K/s

Spread

565K/s

View exact numbers

Test name	Executions per second
✓ Iterate	611,027 Ops/sec
Spread	565,283 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 Purpose:**
The primary goal of this benchmark is to compare the performance of two approaches for iterating over a set of numbers in JavaScript:

1. Using a traditional `for` loop with indexing (`fooSet.add(i)`)
2. Using the spread operator (`...`) to convert the Set into an array, followed by iterating using another `for` loop (`[...fooSet]`)

**Options Compared:**

The benchmark compares two options for iterating over a set of numbers:

1. **Traditional iteration**: The first option uses a traditional `for` loop with indexing (`fooSet.add(i)`). This approach is straightforward and easy to understand, but it may be slower due to the overhead of manual index management.
2. **Spread operator iteration**: The second option uses the spread operator (`...`) to convert the Set into an array, followed by iterating using another `for` loop (`[...fooSet]`). This approach creates a new array and then iterates over it.

**Pros and Cons:**

* **Traditional iteration (for loop with indexing)**:
	+ Pros:
		- Easy to understand and implement
		- No additional memory allocation required
	+ Cons:
		- May be slower due to manual index management
		- More prone to errors due to manual indexing
* **Spread operator iteration**:
	+ Pros:
		- Faster execution time (as shown by the benchmark results)
		- Less prone to errors, as the spread operator handles indexing automatically
	+ Cons:
		- Requires additional memory allocation for the temporary array
		- May not be suitable for very large datasets due to potential memory constraints

**Library and Special JavaScript Features:**
There are no libraries used in this benchmark. However, it's worth noting that the use of the spread operator (`...`) is a relatively recent feature in JavaScript (introduced in ECMAScript 2015). It provides a convenient way to convert Sets into arrays and can improve performance in certain scenarios.

**Benchmark Results:**
The latest benchmark results show that the **spread operator iteration** approach outperforms the traditional `for` loop with indexing. This suggests that using the spread operator can provide a significant performance boost, especially for large datasets.

**Other Alternatives:**
In addition to the two options compared in this benchmark, other alternatives for iterating over a set of numbers might include:

* Using `Array.from()` function, which creates an array from an iterable object (like a Set)
* Using `forEach()` method on the Set object itself
* Implementing a custom iterator or generator function

Set iterator vs Array.from (version: 0)

Comparing performance of: `Iterate vs Spread`

Created: 6 years ago by: Guest

Go to the latest result

Iterate

Spread

Historical Performance Data aggregated from 8 community runs

Desktop Results:

Chrome 8 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Set iterator vs Array.from (version: 0)

Comparing performance of: Iterate vs Spread

Created: 6 years ago by: Guest

Go to the latest result

Iterate

Spread

Historical Performance Data aggregated from 8 community runs

Desktop Results:

Chrome 8 runs

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: `Iterate vs Spread`