src/Date.php
public function diff($date = 'now')
	{
		if ($date instanceof static)
			return $this->date->diff($date->date);
		else if ($date instanceof \DateTime)
			return $this->date->diff($date);
		else if (is_string($date))
			return $this->date->diff(new \DateTime($date, self::$utc));
	//	return is_string($date) ? (new \DateTime($date, self::$utc))->diff($this->date)->days : $date->diff($this->date)->days;
	}
public function diff($date = 'now')
	{
		if ($date instanceof static)
			return $this->date->diff($date->date);
		else if ($date instanceof \DateTime)
			return $this->date->diff($date);
		else if (is_string($date))
			return $this->date->diff(new \DateTime($date, self::$utc));
	//	return is_string($date) ? (new \DateTime($date, self::$utc))->diff($this->date)->days : $date->diff($this->date)->days;
	}
public function diff ( $ date = 'now' ) { if ( $ date instanceof static ) return $ this -> date -> diff ( $ date -> date ) ; else if ( $ date instanceof \ DateTime ) return $ this -> date -> diff ( $ date ) ; else if ( is_string ( $ date ) ) return $ this -> date -> diff ( new \ DateTime ( $ date , self :: $ utc ) ) ; //	return is_string($date) ? (new \DateTime($date, self::$utc))->diff($this->date)->days : $date->diff($this->date)->days;
 }
Returns the difference between two dates

@link	http://php.net/manual/en/datetime.diff.php
Returns the difference between two dates