Benchmark: Array vs Generator comprehension

Script Preparation code:

var map = new Map()
for (let i = 0; i < 500; i++) {
  map.set(i.toString()+"_", i)
}

function* transform(input) {
  for (const [k,v] of input) {
    yield [k+"_2", v]
  }
}

function mapFn([k, v]) {
  return [k+"_2", v]
}

Tests:

Generator
const newMap = new Map(transform(map))
Array
const newMap = new Map([...map].map(mapFn))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Generator
Array

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what is being tested.

**Benchmark Definition:**

The benchmark tests two approaches for creating a new map from an existing map:

1. **Generator Comprehension:** This approach uses a generator function `transform` to create the new map. The generator yields values one at a time, allowing for efficient processing of large datasets.
2. **Array Comprehension:** This approach uses array methods (`Map` and `map`) to create the new map.

**Options Compared:**

The benchmark compares the performance of these two approaches on mobile devices running Firefox Mobile 112 on Android 10.

**Pros and Cons:**

* **Generator Comprehension (Generator):**
	+ Pros:
		- Memory-efficient, as it only yields values one at a time.
		- Can be faster for large datasets due to lazy evaluation.
	+ Cons:
		- May not perform well on older or less powerful devices due to the overhead of creating and managing generators.
* **Array Comprehension (Array):**
	+ Pros:
		- Generally more familiar and easier to implement for developers.
		- Can be faster on older devices with less powerful JavaScript engines, as it avoids the overhead of generator creation.
	+ Cons:
		- More memory-intensive, as it requires creating an array of intermediate values.

**Library:**

None explicitly mentioned in this benchmark. However, it's worth noting that `Map` is a built-in JavaScript object and does not require any additional libraries to use.

**Special JS Features or Syntax:**

* Generators are a feature introduced in ECMAScript 2015 (ES6). They allow functions to generate values over time, rather than computing them all at once.
* The syntax for generator functions (`function*`) is distinct from traditional function definitions.

**Other Considerations:**

When writing benchmarks like this one, it's essential to consider factors such as:

* **Device and browser variability:** Different devices and browsers may have varying levels of performance, memory, or JavaScript engine optimization. Benchmarks should account for these differences to ensure fair comparisons.
* **Benchmarking framework limitations:** The benchmarking framework may introduce overhead or bias that can affect the results.

**Other Alternatives:**

For testing map creation approaches, you could consider alternative benchmarks, such as:

1. Creating maps with different data structures (e.g., objects vs. arrays).
2. Testing map operations (e.g., `get`, `set`, `delete`) for performance and accuracy.
3. Comparing the performance of different map implementations (e.g., `Map` vs. custom array-like objects).

Keep in mind that each benchmark should be designed to address specific use cases or questions, and the choice of alternative benchmarks depends on the context and goals of the testing effort.

Related benchmarks:

Array vs Generator comprehension (version: 0)

Comparing performance of: Generator vs Array

Created: 4 years ago by: Guest

Jump to the latest result

Generator

Array

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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