Benchmark: Capitalize Regex vs Join

Tests:

Regex
const capitalizeFirstLetter = (str) => { if (!str || str.length < 1) return '' let capitalize = str.replace(/(^\w{1})|(-+[a-z])/g, (letter) => letter.toUpperCase()) return capitalize } const str = "Chicago-naperville-elgin, IL-IN-WI" capitalizeFirstLetter(str)
Join
const capitalizeFirstLetter = (string) => { if (!string || string.length < 1) return '' let capitalize = string .split(' ') .map((word) => word.charAt(0).toUpperCase() + word.slice(1)) .join(' ') return capitalize .split('-') .map((word) => word.charAt(0).toUpperCase() + word.slice(1)) .join('-') } const str = "Chicago-naperville-elgin, IL-IN-WI" capitalizeFirstLetter(str)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex
Join

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

The provided benchmark definition and test cases are designed to compare the performance of two approaches: using regular expressions (Regex) versus joining strings.

**Approach 1: Using Regular Expressions**

In this approach, a function `capitalizeFirstLetter` is defined that takes a string as input. The function uses a regular expression to capitalize the first letter of each word in the string. Here's a breakdown of what happens:

* The regular expression `/(^\\w{1})|(-+[a-z])/g` is used to match the first letter of each word.
	+ `^\\w{1}` matches any non-whitespace character at the start of the string (i.e., the first letter).
	+ `-+[a-z]` matches one or more hyphens followed by one or more lowercase letters (i.e., words that start with a hyphen and have an alphabet prefix).
* The `g` flag at the end of the regular expression makes it match all occurrences in the string, not just the first one.
* The `(letter) => letter.toUpperCase()` part of the regular expression is used to uppercase each matched letter.

**Approach 2: Joining Strings**

In this approach, a function `capitalizeFirstLetter` is defined that takes a string as input. The function splits the string into words using spaces as delimiters, capitalizes each word using the `toUpperCase()` method and `charAt(0)`, and then joins the capitalized words back together using spaces as delimiters.

Here's a step-by-step breakdown:

1. `string.split(' ')` splits the string into an array of words.
2. `.map((word) => word.charAt(0).toUpperCase() + word.slice(1))` capitalizes each word by taking the first character and uppercasing it, while keeping the rest of the word unchanged.
3. `.join(' ')` joins the capitalized words back together using spaces as delimiters.

**Pros and Cons**

**Regex Approach:**

Pros:

* Can handle multiple formats for naming (e.g., "Chicago-naperville-elgin, IL-IN-WI" can be matched)
* Can perform complex operations in a single step

Cons:

* May be slower due to the overhead of regular expressions
* Can be less readable and maintainable due to its complexity

**Joining Strings Approach:**

Pros:

* Typically faster due to the simplicity of string manipulation operations
* Easier to read and maintain due to its straightforward logic

Cons:

* Requires manual handling of multiple formats for naming (e.g., spaces, hyphens)
* May not perform as well on large datasets or complex data

**Other Considerations**

* The choice between Regex and joining strings ultimately depends on the specific requirements of the project. If speed is critical, joining strings might be a better approach. However, if handling multiple formats for naming is necessary, Regex might be more suitable.
* Both approaches can be optimized by using techniques like caching, memoization, or parallel processing to improve performance.

**Library Used**

No specific library is mentioned in the provided benchmark definition. However, it's worth noting that the `split()`, `join()`, and `toUpperCase()` methods are built-in JavaScript methods.

**Special JS Feature or Syntax**

The only special syntax used in this benchmark is the use of regular expressions (`/regex/g`). Regular expressions can be complex and challenging to understand for beginners. However, they provide a powerful way to manipulate strings and perform text pattern matching.

I hope this explanation helps! Let me know if you have any further questions.

Latest run results:

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

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_4 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/98.0.4758.85 Mobile/15E148 Safari/604.1

Browser/OS: Chrome Mobile iOS 98 on iOS 15.4

View result in a separate tab

Test name	Executions per second
Regex	1091658.9 Ops/sec
Join	426595.1 Ops/sec

Related benchmarks:

Capitalize Regex vs Join (version: 0)

Comparing performance of: Regex vs Join

Created: 3 years ago by: Guest

Jump to the latest result

Regex

Join

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):