protected function getRequiredType(callable $callback)
	{
		$ref = new \ReflectionFunction($callback);
		
		if($ref->getNumberOfParameters() > 0)
		{
			$params = $ref->getParameters();
			
			if(isset($params[0]) &&  NULL !== ($type = $params[0]->getClass()))
			{
				return $type;
			}
		}
	}
protected function getRequiredType(callable $callback)
	{
		$ref = new \ReflectionFunction($callback);
		
		if($ref->getNumberOfParameters() > 0)
		{
			$params = $ref->getParameters();
			
			if(isset($params[0]) &&  NULL !== ($type = $params[0]->getClass()))
			{
				return $type;
			}
		}
	}
protected function getRequiredType ( callable $ callback ) { $ ref = new \ ReflectionFunction ( $ callback ) ; if ( $ ref -> getNumberOfParameters ( ) > 0 ) { $ params = $ ref -> getParameters ( ) ; if ( isset ( $ params [ 0 ] ) && NULL !== ( $ type = $ params [ 0 ] -> getClass ( ) ) ) { return $ type ; } } }
Determines the type of the first callback argument and returns it.

@param callable $callback
@return string
Determines the type of the first callback argument and returns it .