Benchmark: Multiple Regex Test vs Regex OR

Script Preparation code:

var multipleRegex = [/privacy/i, /accessibility/i, /terms/i];
var orRegex = /(privacy|accessibility|terms)/i;
var links = ['http://site.com/privacy', 'http://site.com/amenities', 'http://site.com/terms-of-use'];

Tests:

Multiple regex
links.forEach((link) => { return multipleRegex.some((regexp) => regexp.test(link)); });
OR regex
links.forEach((link) => { return orRegex.test(link); });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Multiple regex
OR regex

Fastest: N/A

Slowest: N/A

Latest run results:

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

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**Benchmark Overview**

The provided benchmark is designed to compare the performance of two approaches: using multiple regular expressions (regex) and using an "OR" regex (also known as a union).

**Options Compared**

In this benchmark, we have two main options being compared:

1. **Multiple Regex**: This approach involves creating an array of individual regex patterns (`multipleRegex`) and then iterating over the `links` array to test each link against all regex patterns using the `some()` method.
2. **OR Regex** (Union): This approach uses a single regex pattern (`orRegex`) that combines multiple alternatives with the `|` character, allowing it to match any of the individual alternatives.

**Pros and Cons**

Here are some pros and cons for each approach:

* **Multiple Regex**: Pros:
	+ Can be more flexible if you need to test for specific patterns in a link.
	+ May perform better if the regex patterns are relatively simple.
Cons:
	+ Requires more memory allocation and iteration, which can lead to slower performance.
	+ May not take advantage of browser optimizations or caching as effectively.
* **OR Regex** (Union): Pros:
	+ Can be faster due to optimized regex engine execution and caching.
	+ Often results in better code quality due to reduced complexity.

Cons:

* Requires more complex regex pattern creation, which can increase development time.
* May not perform well if the individual alternatives have similar patterns.

**Library Used**

The `some()` method is a built-in JavaScript method that returns `true` as soon as one element of an array passes the test implemented by the provided function. In this benchmark, it's used to iterate over the `links` array and test each link against both regex approaches.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax mentioned in the provided code.

**Benchmark Preparation Code Explanation**

The preparation code creates two variables:

* `multipleRegex`: An array of individual regex patterns (`/privacy/i`, `/accessibility/i`, and `/terms/i`) with the `i` flag to enable case-insensitive matching.
* `orRegex`: A single regex pattern that combines all alternatives using the `|` character (`/(privacy|accessibility|terms)/i`). The `i` flag is used again for case-insensitive matching.

**Benchmark Result Explanation**

The benchmark results show the performance of each approach on a specific test setup:

* **OR Regex**: Chrome 89, Desktop, Mac OS X 10.15.6, with approximately 1.48 executions per second.
* **Multiple Regex**: The same setup, but with around 1.98 executions per second.

It appears that the "OR regex" approach outperforms the multiple regex approach in this specific benchmark. However, keep in mind that performance can vary depending on the complexity of the regex patterns and the specific use case.

Related benchmarks:

Multiple Regex Test vs Regex OR (version: 0)

Comparing performance of: Multiple regex vs OR regex

Created: 4 years ago by: Registered User

Jump to the latest result

Multiple regex

OR regex

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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