public function set($key, $value)
	{
		if ( ! $value instanceof Radio)
		{
			throw new \InvalidArgumentException('Only Radios can be added to a RadioGroup');
		}

		return parent::set($key, $value);
	}
public function set($key, $value)
	{
		if ( ! $value instanceof Radio)
		{
			throw new \InvalidArgumentException('Only Radios can be added to a RadioGroup');
		}

		return parent::set($key, $value);
	}
public function set ( $ key , $ value ) { if ( ! $ value instanceof Radio ) { throw new \ InvalidArgumentException ( 'Only Radios can be added to a RadioGroup' ) ; } return parent :: set ( $ key , $ value ) ; }
Extends the set method to ensure that only Radios can be added to a RadioGroup

@param  string $key
@param  mixed  $value

@return $this

@throws \InvalidArgumentException

@since 2.0
Extends the set method to ensure that only Radios can be added to a RadioGroup