Lua多重继承

Posted 2020-06-13

http://blog.csdn.net/ssihc0/article/details/7742421

代码收藏了,以后用的到
--多重继承
local function search(k,plist)
    for i=1,#plist do
        local v=plist[i][k] --   取一个基类
        if v then return v end
    end
end

function createClass(...)
    local c={};
    local parents={...};

    setmetatable(c,{__index=function(t,k) return search(k,parents) end } );

    c.__index=c;

    function c:new(o)
        o=o or {};
        setmetatable(o,c);
        return o;
    end

    return c;
end

Named={};
function Named:getname()
    return self.name;
end

function Named:setname(n)
    self.name=n;
end

Account={balance=0};

function Account:new(o)
    o= o or {}
    setmetatable(o,self);
    self.__index=self;
    return o;
end

function Account.deposit(self,v)
    self.balance=self.balance+v;
end

function Account:withdraw(v)
    if (v) > self.balance then error "insufficient funds"; end
    self.balance=self.balance-v;
end

NamedAccount=createClass(Account,Named);

user=NamedAccount:new{name="user admin"};
print (user:getname(),user.balance);