Adding filterByRegex method to Laravel Collections

[mohammadrasoulasghari]

Hi everyone! I'm considering contributing a new method to Laravel's Collection class called filterByRegex.

What it does

The method would allow filtering collections using regular expressions in a clean, readable way:

// Filter strings directly
$collection->filterByRegex('/^p/');

// Filter by a specific key
$users->filterByRegex('/@gmail\.com$/', 'email');

// Filter with dot notation for nested arrays
$data->filterByRegex('/PHP/', 'user.profile.bio');

// Filter with a callback
$products->filterByRegex('/2023/', fn($product) => $product->sku);

Why I think it’s useful

While this can be done with the existing filter() method, filterByRegex would:

• Make regex filtering more readable and explicit
• Support dot notation for nested arrays out of the box
• Follow Laravel’s pattern of having specialized filter methods
• Reduce boilerplate when working with regex filters

Questions

1. Would you find this method useful in your projects?
2. Are there any edge cases or parameters I should consider?
3. Is this something that belongs in the core Collection class or would it be better as a macro?

I’d appreciate your thoughts before submitting a PR. Thanks!

[henzeb]

While it is possible using filter, that one uses a closure. I would opt for altering filter to accept a string that executes the regular expression.

[mohammadrasoulasghari]

I disagree with modifying the filter method for these reasons:

1. Backward compatibility - changing filter's behavior risks breaking existing code, even with smart detection between regex and closures.

2. Single Responsibility Principle - filter has a clear purpose of filtering with closures; adding regex logic would increase its responsibilities and complexity.

3. Code clarity - seeing filterByRegex makes the intention immediately clear, while filter doesn't indicate whether it's using regex or a regular condition.