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    <h3>Editing: InputBag.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\HttpFoundation;

use Symfony\Component\HttpFoundation\Exception\BadRequestException;

/**
 * InputBag is a container for user input values such as $_GET, $_POST, $_REQUEST, and $_COOKIE.
 *
 * @author Saif Eddin Gmati &lt;azjezz@protonmail.com&gt;
 */
final class InputBag extends ParameterBag
{
    /**
     * Returns a scalar input value by name.
     *
     * @param string|int|float|bool|null $default The default value if the input key does not exist
     */
    public function get(string $key, mixed $default = null): string|int|float|bool|null
    {
        if (null !== $default &amp;&amp; !\is_scalar($default) &amp;&amp; !$default instanceof \Stringable) {
            throw new \InvalidArgumentException(sprintf('Expected a scalar value as a 2nd argument to &quot;%s()&quot;, &quot;%s&quot; given.', __METHOD__, get_debug_type($default)));
        }

        $value = parent::get($key, $this);

        if (null !== $value &amp;&amp; $this !== $value &amp;&amp; !\is_scalar($value) &amp;&amp; !$value instanceof \Stringable) {
            throw new BadRequestException(sprintf('Input value &quot;%s&quot; contains a non-scalar value.', $key));
        }

        return $this === $value ? $default : $value;
    }

    /**
     * Replaces the current input values by a new set.
     */
    public function replace(array $inputs = [])
    {
        $this-&gt;parameters = [];
        $this-&gt;add($inputs);
    }

    /**
     * Adds input values.
     */
    public function add(array $inputs = [])
    {
        foreach ($inputs as $input =&gt; $value) {
            $this-&gt;set($input, $value);
        }
    }

    /**
     * Sets an input by name.
     *
     * @param string|int|float|bool|array|null $value
     */
    public function set(string $key, mixed $value)
    {
        if (null !== $value &amp;&amp; !\is_scalar($value) &amp;&amp; !\is_array($value) &amp;&amp; !$value instanceof \Stringable) {
            throw new \InvalidArgumentException(sprintf('Expected a scalar, or an array as a 2nd argument to &quot;%s()&quot;, &quot;%s&quot; given.', __METHOD__, get_debug_type($value)));
        }

        $this-&gt;parameters[$key] = $value;
    }

    public function filter(string $key, mixed $default = null, int $filter = \FILTER_DEFAULT, mixed $options = []): mixed
    {
        $value = $this-&gt;has($key) ? $this-&gt;all()[$key] : $default;

        // Always turn $options into an array - this allows filter_var option shortcuts.
        if (!\is_array($options) &amp;&amp; $options) {
            $options = ['flags' =&gt; $options];
        }

        if (\is_array($value) &amp;&amp; !(($options['flags'] ?? 0) &amp; (\FILTER_REQUIRE_ARRAY | \FILTER_FORCE_ARRAY))) {
            throw new BadRequestException(sprintf('Input value &quot;%s&quot; contains an array, but &quot;FILTER_REQUIRE_ARRAY&quot; or &quot;FILTER_FORCE_ARRAY&quot; flags were not set.', $key));
        }

        if ((\FILTER_CALLBACK &amp; $filter) &amp;&amp; !(($options['options'] ?? null) instanceof \Closure)) {
            throw new \InvalidArgumentException(sprintf('A Closure must be passed to &quot;%s()&quot; when FILTER_CALLBACK is used, &quot;%s&quot; given.', __METHOD__, get_debug_type($options['options'] ?? null)));
        }

        return filter_var($value, $filter, $options);
    }
}
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