Benchmark: Regex vs split/includes

Script Preparation code:

var str = '/foo/bar/baz';

Tests:

Regex
/\/bar/g.test(str);
Split and Join
str.split('/').includes('bar');

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

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.109 Safari/537.36

Browser/OS: Chrome 98 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Regex	14731397.0 Ops/sec
Split and Join	11133680.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Overview**

The benchmark compares the performance of two approaches to search for a substring within a string: using regular expressions (`Regex`) versus splitting the string and checking if the substring is included (`Split and Join`).

**Options Compared**

The benchmark tests two options:

1. **Regex**: The first test case uses a regular expression (`/\\/bar/g.test(str);`) to search for the substring `"bar"` within the string `str`. Regular expressions provide a powerful way to match patterns in strings, but they can be computationally expensive.
2. **Split and Join**: The second test case splits the string into an array using the `split()` method (`str.split('/')`) and then checks if the substring is included using the `includes()` method (`includes('bar')`). This approach creates a temporary array and iterates over its elements, which can be less efficient than regular expressions.

**Pros and Cons**

* **Regex:**
	+ Pros:
		- Provides a flexible way to match patterns in strings.
		- Can handle complex cases with anchors, quantifiers, and grouping.
	+ Cons:
		- Can be computationally expensive due to the overhead of compiling and executing regular expressions.
		- May not be as readable or maintainable for simple substring searches.
* **Split and Join:**
	+ Pros:
		- Can be faster than regular expressions for simple substring searches.
		- More readable and maintainable, especially when dealing with complex cases.
	+ Cons:
		- Creates a temporary array, which can lead to memory allocation overhead.
		- Less flexible than regular expressions.

**Library and Purpose**

In the benchmark code, `str` is an example string defined using JavaScript's template literals. It's not a library, but rather a sample input used for demonstration purposes.

**Special JS Feature or Syntax (None)**

There are no special JavaScript features or syntaxes being tested in this benchmark.

**Other Alternatives**

If you want to test alternative approaches, here are some options:

* **Regular Expression Alternatives:**
	+ `String.prototype.indexOf()` instead of `/regex.test(str)`.
	+ `String.prototype.localeCompare()` for case-insensitive matching.
* **Split and Join Alternatives:**
	+ Using `String.prototype.indexOf()` or `String.prototype.lastIndexOf()` to search for the substring.
	+ Using a different separator for splitting the string, such as `\b` (word boundary).

Keep in mind that these alternatives might not provide the same performance or readability benefits as regular expressions or split/join approaches.

Overall, this benchmark provides a simple and straightforward way to compare the performance of two approaches: regular expressions versus split/join. By analyzing the results, developers can gain insights into which approach is more suitable for their specific use cases.

Related benchmarks:

Regex vs split/includes (version: 0)

Comparing performance of: Regex vs Split and Join

Created: 2 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 2 months ago):