Benchmark: Define Regex inline vs not inline...

Tests:

define in function
const run_one_regex = (text) => { ONE_REGEX = /^(?!.* $\s)[\w *()[\]'"/.&–-]+$/gm return ONE_REGEX.test(text); } const text = 'blarb'; for(let i = 0; i < 20000; i++) { run_one_regex(text); }
define outside
ONE_REGEX = /^(?!.* $\s)[\w *()[\]'"/.&–-]+$/gm const run_one_regex = (text) => { return ONE_REGEX.test(text); } const text = 'blarb'; for(let i = 0; i < 20000; i++) { run_one_regex(text); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
define in function
define outside

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 26 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
define in function	453.4 Ops/sec
define outside	2243.9 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Definition**

The benchmark definition is a JSON object that describes two different approaches to defining a regular expression (regex) in JavaScript:

1. "Define Regex inline vs not inline..." - This is the benchmark name, which suggests that we're comparing two methods of defining regex patterns.
2. The script preparation code and HTML preparation code are empty, indicating that the benchmark doesn't require any special setup or configuration.

**Individual Test Cases**

There are two test cases:

1. **Define Regex inline vs not inline... define in function**
This test case defines a regular expression as a variable `ONE_REGEX` inside an anonymous function `run_one_regex`. The regex pattern is defined using the `/gm` flags, which enables global matching (i.e., matches all occurrences of the pattern, not just the first one) and multiline mode. The variable `text` is assigned the value `'blarb'`, and then the function `run_one_regex` is called in a loop 20,000 times.
2. **Define Regex inline vs not inline... define outside**
This test case defines a regular expression as a variable `ONE_REGEX` outside of an anonymous function `run_one_regex`. The regex pattern is defined using the same `/gm` flags as before. However, this time, the `text` variable is assigned the value `'blarb'` inside the `run_one_regex` function.

**Options Compared**

We're comparing two approaches to defining regular expressions:

1. **Inline**: Defining the regex pattern directly inside the `run_one_regex` function.
2. **Out of Line**: Defining the regex pattern outside of the `run_one_regex` function, using a separate variable `ONE_REGEX`.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

**Inline**

Pros:

* Can lead to smaller binary size (since the regex pattern is not stored in memory as a separate entity)
* Can be faster since the compiler/optimizer can optimize the code more effectively

Cons:

* Can make code harder to read and maintain, especially for complex regex patterns
* May lead to slower performance due to the overhead of recompilation or just-in-time (JIT) compilation

**Out of Line**

Pros:

* Easier to read and maintain, since the regex pattern is defined separately from the code that uses it
* Can be faster since the compiler/optimizer can optimize the code more effectively without having to worry about the regex pattern's impact on performance

Cons:

* May lead to larger binary size (since the regex pattern is stored in memory as a separate entity)
* Can slow down performance due to the overhead of loading and executing the regex pattern

**Library Usage**

There isn't any explicit library usage mentioned in the benchmark definition or test cases. However, it's worth noting that some JavaScript engines (like V8) optimize regex patterns using techniques like just-in-time compilation and caching.

**Special JS Features/Syntax**

One special syntax used here is the `/gm` flag, which enables global matching and multiline mode for regular expressions. This flag is not specific to any particular library or framework but rather a standard feature of JavaScript's built-in `RegExp` class.

**Alternatives**

If you're interested in exploring alternative approaches to defining regular expressions, here are some options:

* **Use a regex engine like RegExp**: Instead of using the `/gm` flag, you could use a dedicated regex engine like RegExp. This can provide better performance and features for complex regex patterns.
* **Use a library like jsregex**: There are several libraries available that provide optimized and feature-rich regular expression implementations, such as jsregex.
* **Use a different programming language**: If you're finding JavaScript's regex capabilities inadequate, you could consider using a different programming language with more advanced regex features.

I hope this explanation helps!

Related benchmarks:

Define Regex inline vs not inline... (version: 0)

Comparing performance of: define in function vs define outside

Created: 5 years ago by: Guest

Jump to the latest result

define in function

define outside

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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