Benchmark: split map reverse vs for unshift

Tests:

split map reverse
function convert(num) { return num.toString().split("").map((num) => +num).reverse(); } console.log(convert(564987654));
for unshift
function convert(num) { const numTxt = num.toString(), result = []; for (let i of numTxt) { result.unshift(+i); } return result; } console.log(convert(564987654));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split map reverse
for unshift

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/120.0.0.0 Safari/537.36 Edg/120.0.0.0

Browser/OS: Chrome 120 on Windows

View result in a separate tab

Test name	Executions per second
split map reverse	114973.3 Ops/sec
for unshift	113610.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition**

The provided JSON represents a benchmark definition, which is essentially a script that defines two test cases: "split map reverse" and "for unshift". The script preparation code and HTML preparation code are empty, indicating that these tests do not require any specific setup or configuration.

**Options Compared**

In this benchmark, the two options being compared are:

1. **`map()` with `reverse()`**: This method uses the `split()` function to convert a string into an array, then maps each element to its numeric value using `+`, and finally reverses the array.
2. **For loop with `unshift()`**: This approach uses a for loop to iterate over each character in the input string, converts it to a number using `+`, and then shifts the result onto the beginning of an empty array.

**Pros and Cons**

* **`map()` with `reverse()`**:
	+ Pros: Shorter code, easier to read, and more concise.
	+ Cons: May be slower due to the overhead of creating arrays and performing operations on them.
* **For loop with `unshift()`**:
	+ Pros: Direct iteration over individual characters, potentially faster since it avoids array creation and method calls.
	+ Cons: Longer code, harder to read, and less concise.

In general, the performance difference between these two approaches depends on the specific use case and input data. However, for small strings or numeric inputs, the `for` loop with `unshift()` might be slightly faster due to its direct iteration approach.

**Library Used**

There is no explicit library mentioned in the provided benchmark definition. However, it's possible that a specific library or utility function (e.g., `String.prototype.split()`, `Array.prototype.map()`, etc.) is being used implicitly by the JavaScript engine or interpreter.

**Special JS Feature/Syntax**

This benchmark does not appear to use any special JavaScript features or syntax beyond standard JavaScript language constructs. It's likely that this is intentional, as MeasureThat.net aims to provide a general-purpose benchmarking platform for various JavaScript implementations and versions.

**Alternatives**

For similar benchmarks or comparisons, other options might include:

1. **Using `reduce()` instead of `map()`**: This would involve using the `Array.prototype.reduce()` method to accumulate the reversed array.
2. **Comparing with `split()` on a string array**: Instead of splitting an individual string, this benchmark could compare different approaches for manipulating string arrays (e.g., using `split()`, `map()`, or `forEach()`).
3. **Testing with different data types**: Benchmarking the performance of these methods with varying data types, such as large integers, strings, or objects, to better understand their behavior and potential bottlenecks.

Keep in mind that these alternative benchmarks would require modifications to the existing benchmark definition and might be more complex to set up and run.

Related benchmarks:

split map reverse vs for unshift (version: 0)

Comparing performance of: split map reverse vs for unshift

Created: 2 years ago by: Guest

Jump to the latest result

split map reverse

for unshift

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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