Benchmark: RegExp.test() vs Array.includes()

Tests:

RegExp.test()
const code = /^(?:AE|BH|DZ|EG|IQ|JO|KW|LB|LY|MA|OM|PS|QA|SA|SD|SY|TN)$/i; code.test('SG');
Array.includes()
const code = ['AE','BH','DZ','EG','IQ','JO','KW','LB','LY','MA','OM','PS','QA','SA','SD','SY','TN']; code.includes('SG');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
RegExp.test()
Array.includes()

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'd be happy to help explain the benchmark and its results.

**Benchmark Overview**

The benchmark measures the performance difference between two approaches for testing if a string exists in an array: using `RegExp.test()` versus `Array.includes()`. The benchmark creates two test cases:

1. Using a regular expression (`RegExp.test()`) to check if a specific country code ("SG") is present in a predefined set of country codes.
2. Using the `includes()` method on an array containing the same country codes, with the same target value ("SG").

**Options Compared**

The two options being compared are:

1. **`RegExp.test()`**: This method tests if a given string exists within the specified regular expression pattern. In this case, it's used to check if "SG" is present in the set of country codes.
2. **`Array.includes()`**: This method checks if an element exists in an array. It's used to check if "SG" is present in the array of country codes.

**Pros and Cons**

Here are some pros and cons of each approach:

* **`RegExp.test()`**:
	+ Pros: Can be more efficient for large datasets, as it uses a single pass through the pattern.
	+ Cons: May be slower for smaller datasets due to the overhead of creating and compiling regular expressions.
	+ Also, may require more memory if the dataset is very large.
* **`Array.includes()`**:
	+ Pros: Generally faster and more efficient for small to medium-sized datasets.
	+ Cons: Requires a pass through the array to find the matching element.

In this benchmark, both approaches are relatively simple and don't involve complex logic, so the difference in performance is likely due to factors like array size, JavaScript engine optimizations, and caching.

**Library/Functionality Used**

In the test cases, we're using two built-in functions:

1. **`RegExp()`**: Creates a regular expression object.
2. `includes()`: A method of arrays that checks if an element exists within the array.

These are both part of the standard JavaScript library and don't require any external libraries or modules to be loaded.

**Special JS Features/Syntax**

None are explicitly mentioned in this benchmark.

**Other Alternatives**

If you were considering alternative approaches for testing if a string exists in an array, some options might include:

1. **`Set` data structure**: Using a `Set` object to store unique values and checking membership using the `has()` method.
2. **`indexOf()` method**: Similar to `Array.includes()`, but may have performance differences depending on the JavaScript engine used.
3. **Custom solution**: Depending on the specific requirements, you might need to implement a custom solution using loops or other iteration techniques.

Keep in mind that these alternatives would likely introduce additional overhead and complexity compared to the simple approach of using `Array.includes()`.

Overall, this benchmark provides a basic understanding of how two commonly used methods compare performance in testing if a string exists in an array.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/118.0.0.0 Safari/537.36

Browser/OS: Chrome 118 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
RegExp.test()	37360600.0 Ops/sec
Array.includes()	543237376.0 Ops/sec

Related benchmarks:

RegExp.test() vs Array.includes() (version: 0)

Comparing performance of: RegExp.test() vs Array.includes()

Created: one year ago by: Guest

Jump to the latest result

RegExp.test()

Array.includes()

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):