Benchmark: Regex vs split/join 2

Script Preparation code:

var str = '@babel/core@2.1.1';

Tests:

Regex
str.match(/.+?(?=@)/)[0];
Split and Join
str.split('@').slice(0,-1).join('@');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex
Split and Join

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark measures the performance of two approaches: using a regular expression (`Regex`) to extract a substring, and using `split()`, `slice()`, and `join()` to achieve the same result.

**Options Compared**

Two options are compared:

1. **Regex**: Using a regular expression to match and extract a substring.
2. **Split and Join**: Splitting the string at the specified delimiter (`@`) and joining back together, excluding the last occurrence of the delimiter.

**Pros and Cons of Each Approach**

* **Regex:**
	+ Pros:
		- Can be more flexible and powerful than simple string manipulation methods.
		- Often used for complex pattern matching and validation.
	+ Cons:
		- Can be slower due to the overhead of parsing and compiling regular expressions.
		- May require more memory if dealing with large patterns or input data.
* **Split and Join:**
	+ Pros:
		- Typically faster than regex due to the simplicity and predictability of string manipulation.
		- Often used for simple substring extraction and replacement.
	+ Cons:
		- Less flexible than regex, as it relies on a fixed delimiter and ordering.
		- May not work well with complex or edge cases.

**Library/Technology Used**

The benchmark uses the `@babel/core` library to compile JavaScript code. Specifically, the script preparation code `var str = '@babel/core@2.1.1';` is used to define a string variable named `str`. This library is used for code transpilation and optimization.

**Special JS Feature/Syntax**

There doesn't seem to be any special JavaScript features or syntax being tested in this benchmark. The tests only involve standard JavaScript functions like `match()`, `split()`, and `join()`.

**Other Alternatives**

If you wanted to test alternative approaches, some possibilities could include:

* Using other string manipulation methods, such as `substr()`, `indexOf()`, or `search()`.
* Implementing custom parsing or regular expression engines.
* Utilizing native browser APIs like WebAssembly or SIMD instructions for performance optimization.

Keep in mind that these alternatives might not be directly comparable to the current test cases and may require significant changes to the benchmark setup.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Android 9; Mobile; rv:89.0) Gecko/89.0 Firefox/89.0

Browser/OS: Firefox Mobile 89 on Android

View result in a separate tab

Test name	Executions per second
Regex	2838862.5 Ops/sec
Split and Join	1064619.5 Ops/sec

Related benchmarks:

Regex vs split/join 2 (version: 0)

Comparing performance of: Regex vs Split and Join

Created: 3 years ago by: Guest

Jump to the latest result

Regex

Split and Join

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):