Benchmark: Simple Regex vs split/join

Script Preparation code:

var str = 'Test Case Number One';

Tests:

Regex
str.replace(/ /g, "");
Split and Join
str.split(' ').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 one month ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Purpose**
The main goal of this benchmark is to compare two approaches for removing spaces from a string:

1. Using regular expressions (`str.replace(/ /g, "")`)
2. Splitting the string into an array using `split(' ')` and then joining it back together using `join('')`

These two methods are often used in JavaScript when working with strings.

**Options Compared**
The benchmark is comparing the performance of these two approaches:

* Approach 1: Regular expressions (`str.replace(/ /g, "")`)
	+ This method uses a regular expression to match and replace spaces in the string.
	+ The `/ /g` pattern matches one or more whitespace characters (spaces), and the `replace()` method replaces them with an empty string.
* Approach 2: Splitting and Joining (`str.split(' ').join('')`)
	+ This method splits the string into an array using spaces as separators, and then joins it back together without any separators.

**Pros and Cons of Each Approach**

* **Regular Expressions (Approach 1)**
	+ Pros:
		- Can be used to perform more complex text processing tasks beyond just removing spaces.
		- Can be optimized for performance using flags like `g` (global) or `i` (case-insensitive).
	+ Cons:
		- May have slower performance due to the overhead of compiling a regular expression pattern.
		- Can be more error-prone if not used correctly, as incorrect patterns can cause unexpected behavior.
* **Splitting and Joining (Approach 2)**
	+ Pros:
		- Often faster than using regular expressions for simple string manipulation tasks.
		- More straightforward to understand and implement, especially for beginners.
	+ Cons:
		- Requires additional memory allocation for the array created by splitting, which can be a concern for very large strings.
		- May not be as flexible or powerful as regular expressions.

**Library/Functionality Used**
None are explicitly mentioned in this benchmark. However, it's worth noting that `split()` and `join()` methods typically use internal implementation details to optimize performance, so understanding how these methods work under the hood can provide insight into optimizing string manipulation code.

**Special JS Feature/Syntax**
This benchmark does not appear to use any special JavaScript features or syntax beyond regular expressions and built-in array methods.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.66 Safari/537.36

Browser/OS: Chrome 87 on Windows

View result in a separate tab

Test name	Executions per second
Regex	3377856.2 Ops/sec
Split and Join	2386435.2 Ops/sec

Related benchmarks:

Simple Regex vs split/join (version: 0)

Comparing performance of: Regex vs Split and Join

Created: 4 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 one month ago):