Benchmark: RegEx.test vs. String.includes vs. for

Script Preparation code:

var string = "0123456789";
var regex = /^\d+$/;

Tests:

RegEx.test
regex.test(string);
String.includes
"0123456789".includes(string);
for
for (let i = 0; i < string.length; i++) { const char = +string.charAt(i); if ( char === 0 || char === 1 || char === 3 || char === 4 || char === 5 || char === 6 || char === 7 || char === 8 || char === 9 ) {} }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
RegEx.test
String.includes
for

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

Browser/OS: Chrome 115 on Windows

View result in a separate tab

Test name	Executions per second
RegEx.test	7623568.5 Ops/sec
String.includes	18352424.0 Ops/sec
for	835155.1 Ops/sec

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 Overview**

The benchmark compares three approaches to check if a string contains a specific pattern:

1. `String.includes()`
2. Regular Expressions (`regex.test()`)

We'll also include a manual loop approach (`for`) for comparison purposes.

**Options Compared:**

* **`String.includes()`**: This method uses the "includes" function to search for a substring in a string.
* **Regular Expressions (`regex.test()`)**: This method uses a regular expression pattern to match characters in a string. Regular expressions are a way to describe patterns in strings using special syntax and rules.

**Pros and Cons:**

* `String.includes()`:
	+ Pros:
		- Easy to use and understand
		- Fast and efficient for simple checks
	+ Cons:
		- Can be slow for large strings or complex patterns
		- May not work as expected with certain edge cases (e.g., null or undefined inputs)
* Regular Expressions (`regex.test()`):
	+ Pros:
		- Highly customizable and flexible
		- Can handle complex patterns and edge cases
	+ Cons:
		- Steeper learning curve due to special syntax and rules
		- May be slower than `String.includes()` for simple checks

**Library Used:**

In this benchmark, the library used is not explicitly mentioned. However, it's likely that the JavaScript engine being tested (e.g., V8 in Chrome) has its own implementation of regular expressions.

**Special JS Feature/Syntax:**

There are no special JS features or syntax used in this benchmark.

**Manual Loop Approach (`for`):**

The manual loop approach uses a traditional `for` loop to iterate over the characters in the string and check if each character matches the desired pattern. This approach is generally slower than `String.includes()` or regular expressions due to its iterative nature.

**Pros and Cons:**

* Manual Loop (`for`):
	+ Pros:
		- Easy to understand and implement
	+ Cons:
		- Can be slow and inefficient for large strings or complex patterns

**Other Alternatives:**

Other alternatives to `String.includes()` and regular expressions include:

* Using the `RegExp` object directly (e.g., `new RegExp('\\d+')`)
* Using a library like Lodash's `includes` function
* Using a dedicated string matching algorithm (e.g., Knuth-Morris-Pratt or Rabin-Karp)

Keep in mind that these alternatives may have their own trade-offs and performance characteristics, which are not included in this benchmark.

Overall, the choice of approach depends on the specific use case and requirements. For simple checks, `String.includes()` is a good starting point, while regular expressions provide more flexibility for complex patterns. The manual loop approach can be useful for educational purposes or when specific requirements cannot be met by other methods.

Related benchmarks:

RegEx.test vs. String.includes vs. for (version: 0)

Comparing performance of: RegEx.test vs String.includes vs for

Created: one year ago by: Guest

Jump to the latest result

RegEx.test

String.includes

for

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):