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    <h3>Editing: GithubFlavoredMarkdownConverter.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

declare(strict_types=1);

/*
 * This file is part of the league/commonmark package.
 *
 * (c) Colin O'Dell &lt;colinodell@gmail.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace League\CommonMark;

use League\CommonMark\Environment\Environment;
use League\CommonMark\Extension\CommonMark\CommonMarkCoreExtension;
use League\CommonMark\Extension\GithubFlavoredMarkdownExtension;

/**
 * Converts GitHub Flavored Markdown to HTML.
 */
final class GithubFlavoredMarkdownConverter extends MarkdownConverter
{
    /**
     * Create a new Markdown converter pre-configured for GFM
     *
     * @param array&lt;string, mixed&gt; $config
     */
    public function __construct(array $config = [])
    {
        $environment = new Environment($config);
        $environment-&gt;addExtension(new CommonMarkCoreExtension());
        $environment-&gt;addExtension(new GithubFlavoredMarkdownExtension());

        parent::__construct($environment);
    }

    public function getEnvironment(): Environment
    {
        \assert($this-&gt;environment instanceof Environment);

        return $this-&gt;environment;
    }
}
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