Benchmark: RegEx.exec vs String.test

Script Preparation code:

var string = "test.user@example.com";
var regex = /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;

Tests:

regex.exec
regex.exec(string) !== null;
regex.test
regex.test(string);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex.exec
regex.test

Fastest: N/A

Slowest: N/A

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/605.1.15 (KHTML, like Gecko) Version/17.6 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
regex.exec	7858966.5 Ops/sec
regex.test	11328482.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into explaining the provided benchmark.

**What is tested?**

The benchmark tests two different approaches to validate if a string matches a specific regular expression pattern: `regex.test()` and `regex.exec()`. These functions are part of the JavaScript String prototype, which provides methods for searching and manipulating strings using regular expressions.

**Options compared**

Two options are being compared:

1. **`String.test(string)`**: This method tests whether the entire string matches the regular expression pattern.
2. **`regex.exec(string)`**: This function executes the regular expression pattern on the input string and returns an array of match results, if any.

**Pros and Cons of each approach**

**`String.test(string)`**:

Pros:

* Simpler to implement, as it only needs to perform a single pass through the entire string.
* Can be faster for simple patterns with few alternatives (i.e., no capturing groups).

Cons:

* May not be optimized for performance, especially for complex patterns or large strings.

**`regex.exec(string)`**:

Pros:

* Can handle more complex patterns with multiple capturing groups and anchors.
* Returns an array of match results, which can be useful in some scenarios.

Cons:

* Requires a separate call to `exec()` for each match, which can lead to slower performance compared to `test()`.
* May require more resources (e.g., memory) due to the creation of match objects.

**Library used**

In this benchmark, no external libraries are used. However, if you're interested in exploring other options, some popular regular expression engines for JavaScript include:

* `RegExp`: The built-in JavaScript engine for regular expressions.
* `js-regex`: A library that provides additional features and performance optimizations for regular expressions.

**Special JS feature or syntax**

There is no specific JavaScript feature or syntax used in this benchmark. Both `test()` and `exec()` are standard methods of the JavaScript String prototype.

**Other alternatives**

If you're looking to optimize your code or explore alternative approaches, consider:

* Using a regular expression library like `js-regex` for improved performance.
* Implementing a custom search algorithm using other data structures (e.g., Boyer-Moore or Knuth-Morris-Pratt algorithms).
* Using a different programming language with built-in support for regular expressions, such as Python or Java.

Keep in mind that these alternatives may require significant changes to your code and are not necessarily more efficient or accurate.

Related benchmarks:

RegEx.exec vs String.test (version: 0)

Comparing performance of: regex.exec vs regex.test

Created: one year ago by: Guest

Jump to the latest result

regex.exec

regex.test

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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