Benchmark: regex test1 - MeasureThat.net

Tests:

separate regexs
const envRegex = /\^[a-zA-Z0-9_]+\b/g; const dataRegex = /\$[a-zA-Z0-9_]+\b/g; const dataenvRegex = /(\$|\^)[a-zA-Z0-9_]+\b/g; const str = " background-color: #f7f7f7; opacity: [[ $pageopacity ]]; --r-nonexistentvalue: [[ $noexist ]]; --r-somevar: [[ $somevar ]]; --someevent: [[ @mousemove.clientX[#myelement] ]]; --r-mx: [[ &add(&num(^mouse_clientX), &add(101px,22), 60) ]]px; --r-my: [[ &sub(^mouse_clientY, 20) ]]px;"; str.match(envRegex); str.match(dataRegex);
combined regex
const envRegex = /\^[a-zA-Z0-9_]+\b/g; const dataRegex = /\$[a-zA-Z0-9_]+\b/g; const dataenvRegex = /(\$|\^)[a-zA-Z0-9_]+\b/g; const str = " background-color: #f7f7f7; opacity: [[ $pageopacity ]]; --r-nonexistentvalue: [[ $noexist ]]; --r-somevar: [[ $somevar ]]; --someevent: [[ @mousemove.clientX[#myelement] ]]; --r-mx: [[ &add(&num(^mouse_clientX), &add(101px,22), 60) ]]px; --r-my: [[ &sub(^mouse_clientY, 20) ]]px;"; str.match(dataenvRegex);

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Suite status: <idle, ready to run>

Previous results

Test case name	Result
separate regexs
combined regex

Fastest: N/A

Slowest: N/A

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Autogenerated LLM Summary (model gemma2:9b, generated one year ago):

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This benchmark tests the performance of using regular expressions in JavaScript to extract specific patterns from a string.

**Options Compared:**

* **Separate Regexes:** This approach uses three distinct regular expressions: one for environment variables (`envRegex`), one for data variables (`dataRegex`), and another that combines both (`dataenvRegex`). Each regex is applied individually to the input string (`str`).
* **Combined Regex:** A single regular expression (`dataenvRegex`) is used to capture both environment and data variable patterns within the string.

**Pros/Cons:**

* **Separate Regexes:** 
    * **Pro:** Potentially more readable and maintainable if the regex patterns are significantly different.
    * **Con:** May be less efficient due to multiple regex executions.
* **Combined Regex:**
    * **Pro:** More efficient as it performs a single regex execution, potentially reducing overhead.
    * **Con:**  Can become complex and harder to read if both pattern types are very diverse.

**Other Considerations:**

* **Regex Complexity:** The complexity of the regex itself can significantly impact performance. Simpler regexes will generally execute faster.
* **String Length:** Longer strings will take more time to process, regardless of the approach.
* **Engine Optimization:** Different JavaScript engines (e.g., V8 in Chrome) have varying levels of optimization for regular expressions.

**Alternatives:**

* **Alternative Parsing Techniques:** Depending on the data structure and patterns, techniques like string split/replace or dedicated parsing libraries might be more efficient than regexes.
* **Optimized Regex Libraries:** Specialized libraries like "regexpp" offer performance improvements over built-in JavaScript regex engines.

**Note:** The benchmark results provided show that in this specific case, using a combined regex (`dataenvRegex`) is faster than using separate regexes. However, this may not always be the case and depends on various factors mentioned above.

Related benchmarks:

regex test1 (version: 0)

Comparing performance of: separate regexs vs combined regex

Created: 6 years ago by: Guest

Jump to the latest result

separate regexs

combined regex

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model gemma2:9b, generated one year ago):