Benchmark: endsWith vs Regex-literal

Script Preparation code:

var str = "this is a test"

Tests:

Regex
str.match(/^..._(?:BASE|PRO)$/)
endsWith
str.endsWith("_BASE") || str.endsWith("_PRO")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex
endsWith

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:148.0) Gecko/20100101 Firefox/148.0

Browser/OS: Firefox 148 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
Regex	26366710.0 Ops/sec
endsWith	533838880.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark compares two approaches for checking if a string ends with a specific suffix: using regular expressions (`Regex`) versus using the `endsWith` method.

**Options Compared**

There are two options being compared:

1. **Regex (Regular Expression)**:
	* Uses a pattern to match the string from the beginning (`^`) until a certain character or set of characters is found.
	* In this case, the pattern is `/^..._(?:BASE|PRO)$/`.
2. **endsWith**:
	* A built-in JavaScript method that checks if a string ends with a specified suffix.

**Pros and Cons**

Here are some pros and cons for each approach:

**Regex**

Pros:

* Highly flexible and powerful pattern matching.
* Can match multiple patterns at once.
* Fast performance.

Cons:

* Steeper learning curve due to the complexity of regular expressions.
* May be slower than `endsWith` in some cases, depending on the browser implementation.

**endsWith**

Pros:

* Simple and easy to understand syntax.
* Built-in method means it's implemented efficiently by most browsers.
* Fast performance.

Cons:

* Limited flexibility compared to Regex (e.g., no support for complex patterns).
* May not work in older browsers or environments that don't support `endsWith`.

**Library Used**

In this benchmark, the `RegExp` object is used to create a regular expression pattern. The `RegExp` object provides a way to define and search for patterns in strings.

**Special JavaScript Feature/Syntax**

There are no special JavaScript features or syntax being tested in this benchmark. Both options are straightforward and easy to understand.

**Other Alternatives**

If you needed to test other approaches, some alternatives could be:

* Using a library like `regex-perf` (e.g., for more complex patterns) or `string-performance` (e.g., for string manipulation).
* Testing alternative suffix checking methods, such as `substr()` or `slice()`.
* Comparing the performance of different browsers' implementations of `endsWith`.

Keep in mind that the benchmark's focus is on comparing two specific approaches, so these alternatives are not directly relevant to this particular benchmark.

Related benchmarks:

endsWith vs Regex-literal (version: 0)

Comparing performance of: Regex vs endsWith

Created: 2 years ago by: Guest

Jump to the latest result

Regex

endsWith

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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