Benchmark: flatten reduce vs for of

Tests:

reduce
var flatten = (arr) => arr.reduce((acc, x) => { Array.isArray(x) ? flatten(x).forEach(y => acc.push(y)) : acc.push(x) return acc; }, []) const x = flatten([ [1,2,3], [ [4,5,6], [7,8,9], [[[[[10,11,12]]], [13,14,15]]] ], [[[[[[[[[[[16,17,18]]]]]]]]]]] ]);
for of
function flat(argarr) { const arr = [] for (item of argarr) { if (Array.isArray(item)) arr.push(flat(item)) else arr.push(item) } return arr } const x = flat([ [1,2,3], [ [4,5,6], [7,8,9], [[[[[10,11,12]]], [13,14,15]]] ], [[[[[[[[[[[16,17,18]]]]]]]]]]] ]);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce
for of

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser/OS: Chrome 121 on Windows

View result in a separate tab

Test name	Executions per second
reduce	201878.2 Ops/sec
for of	58945.7 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 JSON and benchmark explanation.

**Benchmark Purpose**

The benchmark tests two approaches to flatten an array: `reduce` and `for...of`. The goal is to compare their performance in flattening nested arrays.

**Options Compared**

1. **Reduce**: This approach uses the `Array.prototype.reduce()` method, which applies a function to each element of an array (in this case, the nested arrays) cumulatively, from left-to-right, so as to reduce it to a single output value.
2. **For...of Loop**: This approach uses a traditional `for` loop with the `foreach` or `of` keyword to iterate over the elements of the nested array.

**Pros and Cons**

* **Reduce**:
	+ Pros: concise code, built-in functionality, potentially faster execution.
	+ Cons: can be less readable for complex arrays, may not work as expected if the initial array is not flat.
* **For...of Loop**:
	+ Pros: more explicit control over iteration, easier to understand for simple cases.
	+ Cons: requires manual management of the loop (e.g., pushing elements to an accumulator array), potentially slower execution.

**Library and Special JS Features**

In this benchmark, there is no specific library used. However, note that `Array.prototype.reduce()` is a built-in JavaScript method, which means it's not explicitly imported or required like in some other contexts.

There are no special JS features mentioned or tested in this benchmark.

**Benchmark Preparation Code and Execution**

The preparation code for each benchmark case is provided in the `Benchmark Definition` section. The execution results are stored in the `RawUAString`, `Browser`, `DevicePlatform`, `OperatingSystem`, `ExecutionsPerSecond`, and `TestName` fields of the latest benchmark result.

**Alternative Approaches**

Other possible approaches to flatten a nested array could include:

1. **Recursive Function**: A custom function that recursively calls itself with each sub-array element.
2. **Using `flat()` Method (if available)**: Some modern browsers and environments support the `Array.prototype.flat()` method, which can be used to flatten arrays in a single step.
3. **Manual Iteration**: Using traditional `for` loops or other iteration mechanisms to iterate over the array elements.

Keep in mind that each approach has its trade-offs in terms of readability, performance, and maintainability.

Related benchmarks:

flatten reduce vs for of (version: 0)

Comparing performance of: reduce vs for of

Created: 2 years ago by: Guest

Jump to the latest result

reduce

for of

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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