private function appendBind($part, $bind) 
	{
		if ($bind === false) return $this;
		
		if (!is_array($bind)) $bind = [$bind]; 
		
		if (!$this->bind[$part]) 
		{
			$this->bind[$part] = $bind;
		}
		else 
		{
			$this->bind[$part] = array_merge($this->bind[$part], $bind);
		}
		
		return $this;
	}