Benchmark: Trim regex string loop

Script Preparation code:

var pat = "/^http.?:\/\/.+\.com/";
var count = 1000;

Tests:

regex replace
for (var i = 0; i < count; i++) { pat.replace(/^\/|\/$/g, ""); }
string substring
for (var i = 0; i < count; i++) { pat.substring(1, pat.length - 1); }
string slice
for (var i = 0; i < count; i++) { pat.slice(1, -1); }

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

string slice

15K/s

string substring

10K/s

regex replace

9K/s

Fastest: string slice (1.7x faster)

View exact numbers

✓ string slice: 14,793 ops/sec
• string substring: 9,933 ops/sec
• regex replace: 8,703 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex replace
string substring
string slice

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Windows

View result in a separate tab

string slice

14K/s

string substring

10K/s

regex replace

8K/s

View exact numbers

Test name	Executions per second
✓ string slice	14,445 Ops/sec
string substring	9,704 Ops/sec
regex replace	8,405 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided benchmark defines three test cases: regex string loop, string substring, and string slice.

The benchmark measures the execution time of different approaches for performing operations on strings. In this case, the string is created with a regular expression pattern `/^http.?:\/\//.com/` which matches HTTP URLs.

**Test Cases and Approaches**

1. **Regex Replace**
	* Approach: Using the `replace()` method to replace specific characters in the string.
	* Code: `pat.replace(/^\\/|\\/$/g, "")`
	* Pros: Can be efficient for replacing multiple occurrences of similar patterns.
	* Cons: May not be optimized for every browser or JavaScript engine.
2. **String Substring**
	* Approach: Using the `substring()` method to extract a part of the string.
	* Code: `pat.substring(1, pat.length - 1)`
	* Pros: Can be efficient for extracting specific parts of the string.
	* Cons: May not be optimized for every browser or JavaScript engine.
3. **String Slice**
	* Approach: Using the `slice()` method to extract a part of the string.
	* Code: `pat.slice(1, -1)`
	* Pros: Can be efficient for extracting specific parts of the string.
	* Cons: May not be optimized for every browser or JavaScript engine.

**Library and Special JS Features**

None of the test cases use any libraries. However, they do utilize special JavaScript features:

* Regular expressions (regex): used to match patterns in the strings.
* Browser-specific features:
	+ `Chrome 120`: uses the Chrome browser's implementation of the methods.
	+ Other browsers may have different implementations or optimizations.

**Other Alternatives**

If you want to explore alternative approaches, here are a few options:

1. **String manipulation using loops**: You can use traditional loop-based string manipulation instead of relying on `replace()`, `substring()`, and `slice()` methods.
2. **Using `indexOf()` and `substr()`**: Instead of using `substring()` or `slice()`, you can use `indexOf()` to find the position of a character and then extract a substring using `substr()`.
3. **Using a third-party library**: While not recommended by MeasureThat.net, you could explore using a library like Lodash or StringPad for string manipulation.

Keep in mind that these alternatives may not be as efficient or optimized as the methods used in the benchmark tests.

Trim regex string loop (version: 0)

Comparing performance of: `regex replace vs string substring vs string slice`

Created: 2 years ago by: Guest

Go to the latest result

regex replace

string substring

string slice

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Trim regex string loop (version: 0)

Comparing performance of: regex replace vs string substring vs string slice

Created: 2 years ago by: Guest

Go to the latest result

regex replace

string substring

string slice

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `regex replace vs string substring vs string slice`