Benchmark: Concat vs flatmapa

Tests:

concat
ids = Array.from(Array(1000).keys()); [].concat(...ids.map(a => Array.from(Array(100).keys())));
flatmap
ids = Array.from(Array(1000).keys()); ids.flatMap(a => Array.from(Array(100).keys()));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
concat
flatmap

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Test name	Executions per second
concat	1220.7 Ops/sec
flatmap	1067.2 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is defined by two test cases: `concat` and `flatmap`. Both tests are designed to measure the performance of JavaScript arrays when concatenating or flattening arrays.

**Options Compared**

In this benchmark, we have two main options:

1. **Concatenation**: The first test case uses `.concat()` method to concatenate an array of 1000 elements (generated by `Array.from(Array(1000).keys())`) with a nested array of 100 elements (generated by `Array.from(Array(100).keys())`).
2. **Flattening**: The second test case uses the `.flatMap()` method to flatten the same nested array.

**Pros and Cons**

Here's a brief analysis of each approach:

* **Concatenation (`concat`)**:
	+ Pros: Easy to implement, widely supported.
	+ Cons: Creates multiple intermediate arrays, which can lead to performance issues for large datasets.
	+ Notes: The `.concat()` method creates new arrays by merging the original array with the new array. This can result in additional memory allocations and garbage collection overhead.
* **Flattening (`flatmap`)**:
	+ Pros: More efficient than concatenation, as it avoids creating intermediate arrays.
	+ Cons: Less widely supported, may require ES6+ support.

**Library Usage**

Neither of the test cases uses a specific library. The `.concat()` and `.flatMap()` methods are part of the standard JavaScript array prototype.

**Special JS Feature/Syntax**

There is no special JavaScript feature or syntax used in these benchmark tests. Both tests use basic JavaScript array operations.

**Other Alternatives**

If you wanted to test alternative approaches, you could consider using:

* **Array.reduce()**: Another method for concatenating arrays, which might be more efficient than `.concat()` for large datasets.
* **String joining**: Concatenating strings using the `+` operator or a library like Lodash's `join()` function.

Keep in mind that these alternatives may not match the exact behavior of `.concat()` and `.flatMap()`, so it's essential to test them specifically for your use case.

Related benchmarks:

Concat vs flatmapa (version: 0)

Comparing performance of: concat vs flatmap

Created: 2 years ago by: Guest

Jump to the latest result

concat

flatmap

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):