lua 里面的面向对象可以使开发看起来更简洁 

local tmp = {};
function tmp:create(id)
    local obj = {
      m_id = id,
	  m_name = "guoyilong ",	
	};
	setmetatable(obj, {__index = tmp});
	return obj;
end 

function tmp:printout()
	self.m_id = self.m_id * 45;
	print("===========> self.m_id ",self.m_id);
end


local tt = tmp:create(45);
print("=====> ",tt.m_id);
tt:printout();

obj 作为类tmp 的属性