How to Repeat Strings and Format Directory Listings in Laravel

When working with strings in Laravel, you may often need to repeat a character or string multiple times. Laravel provides the Str::repeat helper method, which allows you to easily repeat a string a specified number of times. Additionally, this method can be used creatively for formatting directory structures, as we’ll explore in this article.

Understanding the repeat Method

The repeat method is available in Laravel 8, 9 and 11.x and has the following signature:

<?php
 
/**
 * Versions: Laravel 8, 9 and 11.x
 *
 * @return string
 */
public static function repeat(
    string $string,
    int $times
);

This method takes two parameters:

• $string – The string you want to repeat.
• $times – The number of times the string should be repeated.

Basic Example: Repeating a String

A simple use case is generating repeated characters, such as a line of asterisks.

<?php
 
use Illuminate\Support\Str;
 
echo Str::repeat('*', 10); // Output: **********

Alternatively, you can use fluent string instances:

<?php
 
echo (string) str('*')->repeat(10); // Output: **********

Practical Use Case: Formatting a Directory Structure

The Str::repeat method is especially useful when formatting text output. Let’s use it to create a function that * pretty-prints a directory listing recursively*.

<?php
 
use Illuminate\Support\Str;
 
function printDirectory($directory, $depth = 1)
{
    $output = '';
    $ignoreFiles = ['.', '..'];
 
    if ($depth == 1) {
        $output = '/' . basename($directory);
    } else {
        $output = Str::repeat(' ', $depth) . '/' . basename($directory);
    }
 
    $output .= collect(scandir($directory))
        ->filter(fn($file) => !in_array($file, $ignoreFiles))
        ->map(function ($item) use ($directory, $depth) {
            $fullPath = $directory . '/' . $item;
 
            if (is_dir($fullPath)) {
                return "\n" . printDirectory($fullPath, $depth + 1);
            } else {
                return "\n" . Str::repeat(' ', $depth) . ' - ' . $item;
            }
        })
        ->join('');
 
    return $output;
}

How It Works

• The function scans a directory and retrieves all files and subdirectories.
• It uses Str::repeat(' ', $depth) to indent nested items based on their depth.
• When a directory is encountered, the function calls itself recursively, increasing the depth each time.

Example Output

If we call this function on Laravel’s resources directory:

<?php
 
echo printDirectory(resource_path());

We get the following output:

/resources
 /css
  - app.css
 /js
  - app.js
  - bootstrap.js
 /views
  - welcome.blade.php

And for the public directory:

/public
 /css
  - app.css
 /js
  - app.js
  - bootstrap.js

This neatly formatted output provides a clear overview of the directory structure.

Conclusion

The Str::repeat helper method in Laravel is a simple yet powerful tool for repeating strings. Whether you’re generating repeated characters or formatting hierarchical data like directory structures, this method provides a clean and efficient solution.