php-ml/src/FeatureExtraction/StopWords.php

<?php

declare(strict_types=1);

namespace Phpml\FeatureExtraction;

use Phpml\Exception\InvalidArgumentException;

class StopWords
{
    /**
     * @var array
     */
    protected $stopWords = [];

    public function __construct(array $stopWords)
    {
        $this->stopWords = array_fill_keys($stopWords, true);
    }

    public function isStopWord(string $token): bool
    {
        return isset($this->stopWords[$token]);
    }

    public static function factory(string $language = 'English'): self
    {
        $className = __NAMESPACE__."\\StopWords\\{$language}";

        if (!class_exists($className)) {
            throw new InvalidArgumentException(sprintf('Can\'t find "%s" language for StopWords', $language));
        }

        return new $className();
    }
}