Benchmark: test regex js - MeasureThat.net

Script Preparation code:

var a = "/1231231"
var b = "121312321"

Tests:

regex
console.log(/^\//.test(a)); console.log(/^\//.test(b));
noregex
console.log(a.startsWith("/")) console.log(b.startsWith("/"))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex
noregex

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.162 Safari/537.36

Browser/OS: Chrome 80 on Mac OS X 10.15.4

View result in a separate tab

Test name	Executions per second
regex	40951.0 Ops/sec
noregex	41718.7 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of MeasureThat.net and explore what's being tested in this benchmark.

**Benchmark Definition**

The provided JSON represents the benchmark definition, which includes:

* `Script Preparation Code`: This code is executed before running the test cases. In this case, it defines two variables: `a` and `b`, both containing string literals.
* `Html Preparation Code`: There's no HTML preparation code specified in this example.

**Individual Test Cases**

There are two test cases:

1. **"regex"`**: This test case runs a single JavaScript statement that uses the `/` character as a regular expression (regex) to search for a pattern in both strings `a` and `b`. The `console.log()` statements will output whether or not the regex matches.
2. **"noregex"`**: This test case also runs two `console.log()` statements, but instead of using regex, it uses the `startsWith()` method to check if each string starts with `/`.

**Options Compared**

The benchmark is comparing the performance of these two approaches:

* Using regex (`"regex"` test case)
* Not using regex (`"noregex"` test case)

**Pros and Cons of Each Approach:**

**Regex (":regex")**

Pros:

* Robust pattern matching capabilities
* Can handle complex patterns

Cons:

* Typically slower than non-regex approaches due to the overhead of parsing and executing the regex syntax
* May have performance implications for certain use cases, like string manipulation or data validation

**Non-Regex (`"noregex"`)**

Pros:

* Generally faster than regex due to fewer operations required (string comparison)
* Suitable for simple string matching tasks

Cons:

* Less powerful pattern matching capabilities compared to regex
* May not be suitable for complex pattern matching requirements

**Library: `startsWith()`**

In the `"noregex"` test case, the `startsWith()` method is used. This is a built-in JavaScript method that checks if a string starts with a specified value. It's a simple and efficient way to perform this type of comparison.

**Special JS Feature/ Syntax: None**

There are no special JavaScript features or syntaxes being tested in this benchmark. Both test cases use standard JavaScript methods and operators.

**Other Alternatives**

If you're looking for alternative approaches to string matching, consider the following:

* Using a dedicated string manipulation library like `lodash.string`
* Utilizing a regex engine with improved performance, such as ` RegExp` (though still slower than non-regex approaches)
* Leveraging hardware-accelerated string comparisons on some platforms

Keep in mind that the choice of approach depends on your specific use case and performance requirements.

I hope this explanation helps you understand what's being tested in this MeasureThat.net benchmark!

Related benchmarks:

test regex js (version: 0)

coucou

Comparing performance of: regex vs noregex

Created: 4 years ago by: Guest

Jump to the latest result

regex

noregex

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):