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    <h3>Editing: IterableType.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php declare(strict_types=1);
/*
 * This file is part of sebastian/type.
 *
 * (c) Sebastian Bergmann &lt;sebastian@phpunit.de&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace SebastianBergmann\Type;

use function assert;
use function class_exists;
use function is_iterable;
use ReflectionClass;
use ReflectionException;

final class IterableType extends Type
{
    /**
     * @var bool
     */
    private $allowsNull;

    public function __construct(bool $nullable)
    {
        $this-&gt;allowsNull = $nullable;
    }

    /**
     * @throws RuntimeException
     */
    public function isAssignable(Type $other): bool
    {
        if ($this-&gt;allowsNull &amp;&amp; $other instanceof NullType) {
            return true;
        }

        if ($other instanceof self) {
            return true;
        }

        if ($other instanceof SimpleType) {
            return is_iterable($other-&gt;value());
        }

        if ($other instanceof ObjectType) {
            $className = $other-&gt;className()-&gt;qualifiedName();
            assert(class_exists($className));

            try {
                return (new ReflectionClass($className))-&gt;isIterable();
                // @codeCoverageIgnoreStart
            } catch (ReflectionException $e) {
                throw new RuntimeException(
                    $e-&gt;getMessage(),
                    (int) $e-&gt;getCode(),
                    $e
                );
                // @codeCoverageIgnoreEnd
            }
        }

        return false;
    }

    public function name(): string
    {
        return 'iterable';
    }

    public function allowsNull(): bool
    {
        return $this-&gt;allowsNull;
    }

    /**
     * @psalm-assert-if-true IterableType $this
     */
    public function isIterable(): bool
    {
        return true;
    }
}
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