Benchmark: String split using regex vs string v3

Script Preparation code:

var string = 'salut comment ca  va moi test pa adsk ldsj dkjasb kdaj akdajkda     dkna dlkas mas '

Tests:

Split by regex
var res = string.split(/\btest\b/)
Split by string
var res = string.split('test')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Split by regex
Split by string

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:134.0) Gecko/20100101 Firefox/134.0

Browser/OS: Firefox 134 on Linux

View result in a separate tab

Test name	Executions per second
Split by regex	13888588.0 Ops/sec
Split by string	16623416.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its options.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmarking test case, specifically measuring the performance of string splitting using two different approaches: regular expressions (regex) and plain string slicing. The test uses a predefined string variable `string` that contains a long sequence of characters with the substring "test" embedded within it.

**Options Compared**

The benchmark compares the performance of two options:

1. **Split by Regex**: This approach uses the `split()` method with a regular expression to split the input string into substrings.
2. **Split by String**: This approach uses the `split()` method without any arguments, relying on the default behavior to split the string at whitespace characters (spaces and tabs) or use an empty separator.

**Pros and Cons**

Here's a brief summary of each option:

* **Split by Regex**:
	+ Pros: More flexible and powerful than plain string splitting, as it can handle complex patterns and escaped special characters.
	+ Cons: Slower due to the overhead of compiling and executing the regex pattern.
* **Split by String**:
	+ Pros: Faster and more lightweight, as it doesn't require the additional processing time for regex compilation.
	+ Cons: Less flexible and may not work correctly with non-whitespace characters or escaped special characters.

**Library**

In this benchmark, no specific library is required or used beyond the built-in JavaScript `split()` method. However, in general, libraries like RegEx (e.g., `regex.js`) can be used to simplify regex syntax and provide more features.

**Special JS Feature/Syntax**

This benchmark uses the `var` keyword for variable declaration, which was a common practice in early versions of JavaScript. Modern JavaScript recommends using `let` or `const` instead, as they offer better scoping and binding behavior.

In summary, this benchmark allows users to compare the performance of two string splitting approaches: one using regular expressions and another relying on whitespace characters. The choice between these options depends on the specific use case and performance requirements.

**Other Alternatives**

If you need more advanced or specialized string splitting capabilities, consider using:

1. **String.prototype.split() with a custom regex pattern**: You can create a custom regex pattern using the `RegExp` constructor to achieve more complex splitting scenarios.
2. **Third-party libraries like RegEx**: As mentioned earlier, RegEx provides a simpler and more readable way to work with regular expressions in JavaScript.

Keep in mind that for most use cases, the built-in `split()` method or simple string slicing should suffice. However, if you need more advanced features or customization options, consider using one of these alternatives.

Related benchmarks:

String split using regex vs string v3 (version: 0)

Comparing performance of: Split by regex vs Split by string

Created: 4 years ago by: Guest

Jump to the latest result

Split by regex

Split by string

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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