Benchmark: foreach vs map - creating new based on

Script Preparation code:

var values = new Array(10000);
for (var i = 0; i < values.length; i++) values[i]=i;

Tests:

foreach
var agg1 = []; var agg2 = []; values.forEach(v => { agg1.push(v + 1); agg2.push(v + 2); });
map
var agg1 = values.map(v => v + 1); var agg2 = values.map(v => v + 2);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
foreach
map

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's dive into the world of JavaScript microbenchmarks!

**What is tested?**

The provided JSON represents a benchmark that tests two approaches for iterating over an array and performing operations on its elements: `forEach` and `map`.

In this specific case, both approaches are creating a new array (`agg1` and `agg2`) by adding 1 and 2 to each element of the original array (`values`). The goal is to measure which approach is faster.

**Options compared**

The two options being compared are:

1. **forEach**: This method iterates over an array using a traditional loop, executing a callback function for each element.
2. **map**: This method creates a new array by applying a provided mapping function to each element of the original array.

**Pros and Cons of each approach**

* **forEach**
	+ Pros:
		- More explicit control over the iteration process
		- Can be more readable for simple iterations
	+ Cons:
		- Requires manual management of indices (e.g., `i` in the example)
		- May incur additional overhead due to the loop and index manipulation
* **map**
	+ Pros:
		- Creates a new array, eliminating the need for manual iteration and index management
		- More concise and expressive, especially for simple transformations
	+ Cons:
		- May incur overhead due to creating a new array
		- Can be less readable for complex iterations

**Library usage**

There is no explicit library mentioned in the benchmark definition. However, it's worth noting that both `forEach` and `map` are built-in methods of JavaScript arrays, so they don't require any external libraries.

**Special JS feature or syntax**

This benchmark does not utilize any special JavaScript features or syntax beyond the standard `forEach` and `map` methods. No ES6+ features like arrow functions, template literals, or destructuring are used in this example.

**Other alternatives**

If you wanted to compare other iteration approaches for creating a new array, some alternatives could include:

* **reduce**: A more complex method that can be used for aggregating values.
* **filter**: A method for filtering elements based on a condition.
* **forEach** with a custom loop implementation (e.g., using a `for` loop with an index variable).

For a more comprehensive benchmarking approach, you might also consider testing:

* Different array lengths and sizes
* Iteration over different types of arrays (e.g., objects, sets)
* Using parallel execution or concurrent iteration

Keep in mind that the choice of alternatives will depend on the specific use case and requirements of your benchmark.

Related benchmarks:

foreach vs map - creating new based on (version: 0)

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Comparing performance of: foreach vs map

Created: 5 years ago by: Guest

Jump to the latest result

foreach

map

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):