Benchmark: split.includes vs regex boundary

Script Preparation code:

var str = "AB CD EF GH IJ KL";
var needle = "CD";
var regex = /\bCD\b/;
var escapeRegEx = (string) => string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')

Tests:

str.split.includes
str.split(' ').includes(needle);
regex - create inline
str.match(escapeRegEx(needle))
regex - create first
str.match(regex)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
str.split.includes
regex - create inline
regex - create first

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Windows

View result in a separate tab

Test name	Executions per second
str.split.includes	7773167.5 Ops/sec
regex - create inline	3112663.0 Ops/sec
regex - create first	9836886.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the provided benchmark.

**Benchmark Definition**

The benchmark is designed to compare three different approaches for testing whether a specific string (`needle`) is included in another string (`str`):

1. Using the `includes()` method on an array returned by the `split()` method, which splits the string into words.
2. Creating a regular expression (regex) pattern and using it with the `match()` method to search for the needle within the original string.
3. Creating an inline regex pattern using the `escapeRegEx()` function.

**Options Compared**

The three options are compared as follows:

* **str.split(' ').includes(needle)**: This option splits the input string into words and then checks if the needle is included in that array of words.
* **str.match(escapeRegEx(needle))**: This option creates an inline regex pattern using the `escapeRegEx()` function, which escapes special characters in the needle to create a safe regex pattern. The resulting pattern is then used with the `match()` method to search for the needle within the original string.
* **str.match(regex)**: This option creates a standalone regex pattern using the `/\\bCD\\b/` syntax (explained later). The resulting pattern is then used with the `match()` method to search for the needle within the original string.

**Pros and Cons**

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

* **str.split(' ').includes(needle)**:
	+ Pros: Simple and easy to understand, works well for short strings.
	+ Cons: May not be efficient for longer strings due to the overhead of splitting and searching.
* **str.match(escapeRegEx(needle))**:
	+ Pros: Efficient and scalable, can handle longer strings.
	+ Cons: Requires an additional function (`escapeRegEx()`) which may add complexity.
* **str.match(regex)**:
	+ Pros: Can be efficient for simple regex patterns, eliminates the need for `escapeRegEx()`.
	+ Cons: May not work well for more complex regex patterns or longer strings.

**Library and Purpose**

The `escapeRegEx()` function is used to escape special characters in the needle to create a safe regex pattern. This is necessary because some special characters have a specific meaning in regex, such as `.`, `*`, and `?`. By escaping these characters, the resulting pattern will match only the intended substring.

**Special JS Feature or Syntax**

The benchmark uses the following JavaScript features:

* **Template literals**: Used in the `"var str = \\u201cAB CD EF GH IJ KL\\u201d;"` line to create a string with escaped quotes.
* **Arrow functions**: Used in the `"var escapeRegEx = (string) => string.replace(/[.*+?^${}()|[\\]\\\\]/g, \\\\$&')"` line to define the `escapeRegEx()` function.

Other Alternatives

If you're interested in exploring alternative approaches or optimizations, here are a few ideas:

* **Use `String.prototype.includes()` instead of `Array.prototype.includes()`**: This might be slightly faster for very large strings.
* **Experiment with different regex patterns**: Try using different modifiers (e.g., `g`, `i`) to see if they improve performance.
* **Try using a different string splitting method**: Instead of `split(' ')`, you could try `str.split('CD')` or another approach.

Keep in mind that these are just suggestions, and the best approach will depend on your specific use case and performance requirements.

Related benchmarks:

split.includes vs regex boundary (version: 0)

Comparing performance of: str.split.includes vs regex - create inline vs regex - create first

Created: one year ago by: Guest

Jump to the latest result

str.split.includes

regex - create inline

regex - create first

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):