PHP Stemmer

A strictly-typed stemming library for PHP 8.3+. This library helps reduce words to their base form, which is essential for quality full-text search, indexing, or text analysis.

✨ Features

• Modern PHP: Fully utilizes PHP 8.3+ features (Enums, strict typing).
• Multiple Modes:
  • LIGHT: Removes only basic suffixes (plurals, cases). Ideal for result highlighting (words remain readable).
  • AGGRESSIVE: Reduces words to their morphological root. Ideal for search indexes.
• Customizable: Easily extend with your own language drivers.
• Supported Languages: Czech, English

🚀 Installation

You can install the library via Composer:

composer require dompat/stemmer

📖 Usage

Basic Example

use Dompat\Stemmer\Stemmer;
use Dompat\Stemmer\Driver\CzechDriver;
use Dompat\Stemmer\Driver\EnglishDriver;
use Dompat\Stemmer\Enum\StemmerMode;

// 1. Using the main Stemmer manager
$stemmer = new Stemmer([
    new CzechDriver('cs'),
    new EnglishDriver('en'),
]);

echo $stemmer->stem('městě', 'cs'); // "město"
echo $stemmer->stem('working', 'en'); // "work"

// 2. Using drivers directly (optional)
$czechDriver = new CzechDriver('cs');
echo $czechDriver->stem('nejkrásnějšímu', StemmerMode::AGGRESSIVE); // "krásn"

// 3. Custom locale for specific needs (e.g., Slovak)
$skDriver = new CzechDriver('sk');
echo $skDriver->stem('meste', StemmerMode::LIGHT); // "mesto"

Runtime Driver Registration

use Dompat\Stemmer\Stemmer;
use Your\Custom\CustomDriver;

$stemmer = new Stemmer();
$stemmer->addDriver(new CustomDriver('xy'));

echo $stemmer->stem('word', 'xy');

🌍 Supported Languages

Missing a language? Feel free to create your own driver by implementing DriverInterface and submit a Pull Request!

⚙️ Mode Differences

LIGHT

Suitable for autocomplete and word highlighting in text. Removes only the most necessary suffixes so the word remains understandable to the user.

AGGRESSIVE

Suitable for search indexing. Reduces the word to its core, increasing search relevance across different word forms.

Comparison Table

🛠 Development and Testing

If you want to contribute to the library, you can run tests and static analysis:

# Run tests
vendor/bin/phpunit tests

# Static analysis (PHPStan)
vendor/bin/phpstan analyse

📄 License

This library is licensed under the MIT License.