public function registerValidators(AgaviValidationManager $vm, array $depends, array $parameters=array())
	{
		$this->value = isset($parameters[$this->name]);
		$vm->createValidator(
			'AgaviIssetValidator',
			array($this->name),
			array('' => 'field is required'),
			array(
				'translation_domain' => AgaviConfig::get('Form.TranslationDomain'),
				'required' => (bool) $this->required,
				'depends' => $depends
			)
		);
	}