Benchmark: asdf concat() vs flat()

Tests:

reduce + Array.prototype.concat
var params = [[ 1, 2 ], [ "hello", true, 7 ]]; var other = [].concat(...params);
Array.prototype.flat
var params = [[1, 2, params], [ "hello", true, 7 ]]; var other = params.flat();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce + Array.prototype.concat
Array.prototype.flat

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:73.0) Gecko/20100101 Firefox/73.0

Browser/OS: Firefox 73 on Mac OS X 10.14

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Test name	Executions per second
reduce + Array.prototype.concat	6022980.5 Ops/sec
Array.prototype.flat	7283482.5 Ops/sec

Autogenerated LLM Summary (model llama3.1:latest, generated 2 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the details of this benchmark.

**Benchmark Overview**

The benchmark compares two approaches to concatenating arrays in JavaScript:

1. Using `Array.prototype.concat()` with the spread operator (`...`) to concatenate multiple arrays.
2. Using the new ES6 method, `Array.prototype.flat()`, to flatten a nested array.

**Test Case 1: Reduce + Array.prototype.concat**

In this test case, we have a nested array `params` and use `reduce()` in combination with `concat()` to merge all sub-arrays into a single array. The code is:
```javascript
var params = [[ 1, 2 ], [ "hello", true, 7 ]];
var other = [].concat(...params);
```
Here's what happens:

* We create a nested array `params` with two sub-arrays: `[1, 2]` and `["hello", true, 7]`.
* We use `reduce()` to merge all sub-arrays into a single array.
* The spread operator (`...`) is used to "unwrap" the sub-arrays from the parent array.
* Finally, we concatenate the result with an empty array using `concat()`.

**Test Case 2: Array.prototype.flat**

In this test case, we use the new ES6 method, `Array.prototype.flat()`, to flatten a nested array directly. The code is:
```javascript
var params = [[1, 2, params], [ "hello", true, 7 ]];
var other = params.flat();
```
Here's what happens:

* We create a nested array `params` with two sub-arrays: `[1, 2, params]` and `["hello", true, 7]`.
* The `flat()` method is called on the parent array to flatten it directly.

**Library/Feature Used**

No external library or special JavaScript feature is used in these test cases. They rely solely on built-in JavaScript methods and syntax.

**Pros/Cons Comparison**

| Approach | Pros | Cons |
| --- | --- | --- |
| Reduce + Array.prototype.concat | More explicit, easy to read | Less efficient (as seen in the benchmark results) |
| Array.prototype.flat | Efficient (as seen in the benchmark results), concise code | Less well-known, may require more research |

**Other Considerations**

* `Array.prototype.flat()` is a more modern and efficient way to flatten arrays.
* However, it's essential to be aware that `flat()` only flattens up to one level. If you need to flatten deeply nested arrays (more than one level), using `reduce()` or another approach might be necessary.

**Alternatives**

If the benchmark results show significant performance differences between these approaches, alternative solutions could include:

* Using a library like Lodash's `flatten()` method for more complex use cases.
* Implementing custom flattening logic with recursive functions or other methods.
* Considering specific use cases where one approach might be more suitable than the other.

Related benchmarks:

asdf concat() vs flat() (version: 0)

Compare the new ES6 spread operator with the traditional concat() method

Comparing performance of: reduce + Array.prototype.concat vs Array.prototype.flat

Created: 4 years ago by: Guest

Jump to the latest result

reduce + Array.prototype.concat

Array.prototype.flat

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated 2 months ago):