Benchmark: test forEach and push vs map unshift 2

Tests:

for and push
const arr = [1,2,3,4,5,6,7,8,9,10] const res = []; arr.forEach((el)=> res.push(el+1));
map and unshift
const arr = [1,2,3,4,5,6,7,8,9,10] let res = []; res = arr.map((el)=> el+1); res.unshift(0);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for and push
map and unshift

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

Browser/OS: Chrome 115 on Windows

View result in a separate tab

Test name	Executions per second
for and push	27212556.0 Ops/sec
map and unshift	5864728.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided JSON benchmark.

The main goal of this benchmark is to compare the performance of two approaches for manipulating arrays:

1. `forEach` with `push`
2. `map` followed by `unshift`

**Options Compared**

In the first approach, `forEach`, an array element is pushed onto another array (`res`) using the `push` method. In the second approach, `map`, a new array is created containing modified elements of the original array (`arr`) and then the resulting array has its first element prepended with `0` using `unshift`.

**Pros and Cons**

### For Each with Push

* **Pros:**
	+ Simple to understand and implement.
	+ No extra memory allocation required for the resulting array.
* **Cons:**
	+ Can be slower due to the use of `push`, which involves shifting elements in the destination array.

### Map followed by Unshift

* **Pros:**
	+ Creates a new array, which can lead to better performance and less memory pressure.
	+ Allows for direct modification of the resulting array without needing to iterate over it again.
* **Cons:**
	+ Requires extra memory allocation for the newly created array.
	+ Can be slower due to the use of `map` followed by `unshift`.

**Other Considerations**

In addition to performance, we should also consider:

* Memory usage: The first approach might consume more memory than the second one, especially when dealing with large arrays.
* Readability and maintainability: While the first approach is simple, the second one might be considered more readable due to its use of a single `map` operation followed by a clear `unshift`.

**Library Usage**

Neither of the approaches relies on any external libraries. However, if we were to consider using libraries for optimization or simplification, some options could include:

* Lodash: Provides functions like `flattenArray` and `merge`, which might simplify array manipulation.
* Ramda: Offers functional programming utilities, including those for array operations.

**Special JS Features/Syntax**

This benchmark does not use any special JavaScript features or syntax beyond the standard ES6+ syntax.

Related benchmarks:

test forEach and push vs map unshift 2 (version: 0)

test forEach and push vs map unshift

Comparing performance of: for and push vs map and unshift

Created: one year ago by: Guest

Jump to the latest result

for and push

map and unshift

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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