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

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Mime;

use Symfony\Component\Mime\Exception\LogicException;

/**
 * @author Fabien Potencier &lt;fabien@symfony.com&gt;
 */
class RawMessage
{
    private $message;

    public function __construct(iterable|string $message)
    {
        $this-&gt;message = $message;
    }

    public function toString(): string
    {
        if (\is_string($this-&gt;message)) {
            return $this-&gt;message;
        }
        if ($this-&gt;message instanceof \Traversable) {
            $this-&gt;message = iterator_to_array($this-&gt;message, false);
        }

        return $this-&gt;message = implode('', $this-&gt;message);
    }

    public function toIterable(): iterable
    {
        if (\is_string($this-&gt;message)) {
            yield $this-&gt;message;

            return;
        }

        $message = '';
        foreach ($this-&gt;message as $chunk) {
            $message .= $chunk;
            yield $chunk;
        }
        $this-&gt;message = $message;
    }

    /**
     * @throws LogicException if the message is not valid
     */
    public function ensureValidity()
    {
    }

    public function __serialize(): array
    {
        return [$this-&gt;toString()];
    }

    public function __unserialize(array $data): void
    {
        [$this-&gt;message] = $data;
    }
}
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