如何在假定类中传递变量？

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我的赋值运算符有问题。 我正在编写一个程序以加载一些参数，例如int，double和我自己的类“ quat”。

所以我写一个函数'loadParam'如下：

#include <math.h>
#include <iostream>
#include <typeinfo>
#include <string>

class quat
{
    public:
    quat()
    {

    }
    quat(double r, double i, double j, double k)
    {
        r_ = r;
        i_ = i;
        j_ = j;
        k_ = k;
    }
    friend std::ostream& operator<<(std::ostream& os, const quat& q)
    {
        os << q.r_ << ", " << q.i_ << ", " << q.j_ << ", " << q.k_;
        return os;
    }
    quat Inv()
    {
        quat q;
        double L = sqrt(this->r_*this->r_ + this->i_*this->i_ + this->j_*this->j_ + this->k_*this->k_);
        q.r_ = this->r_/L;
        q.i_ = -1*this->i_/L;
        q.j_ = -1*this->j_/L;
        q.k_ = -1*this->k_/L;
    }
    private:
        double r_;
        double i_;
        double j_;
        double k_;
};



class myClass
{
    public:
        myClass(const int& p1, const std::string& p2, const quat& p3)
        {
            loadParam(p1, param1_);
            loadParam(p2, param2_);
            loadParam(p3, param3_);

            std::cout << "param1: " << param1_ << std::endl;
            std::cout << "param2: " << param2_ << std::endl;
            std::cout << "param3: " << param3_ << std::endl;
        }
    private:
        template<typename T, typename S>void loadParam(T& in, S& param)
        {
            if(typeid(param) == typeid(int))
            {
                std::cout << "Load integer" << std::endl;
                param = in;
            }
            else if(typeid(param) == typeid(std::string))
            {
                std::cout << "Load string" << std::endl;
                param = in;
            }
            else if(typeid(param) == typeid(quat))
            {
                std::cout << "Load quat" << std::endl;
                param = in.Inv();
            }
        }
        int param1_;
        std::string param2_;
        quat param3_;
};


int main() {
    quat q;
    myClass a(1, "test", q);

    return 0;
}

我得到

/home/yuan/Code/test/src/common.cpp: In instantiation of ‘void myClass::loadParam(T&, S&) [with T = const int; S = int]’:
/home/yuan/Code/test/src/common.cpp:48:25:   required from here
/home/yuan/Code/test/src/common.cpp:72:11: error: request for member ‘Inv’ in ‘in’, which is of non-class type ‘const int’
     param = in.Inv();
           ^
/home/yuan/Code/test/src/common.cpp: In instantiation of ‘void myClass::loadParam(T&, S&) [with T = const std::__cxx11::basic_string<char>; S = std::__cxx11::basic_string<char>]’:
/home/yuan/Code/test/src/common.cpp:49:25:   required from here
/home/yuan/Code/test/src/common.cpp:72:11: error: ‘const class std::__cxx11::basic_string<char>’ has no member named ‘Inv’
/home/yuan/Code/test/src/common.cpp: In instantiation of ‘void myClass::loadParam(T&, S&) [with T = const quat; S = quat]’:
/home/yuan/Code/test/src/common.cpp:50:25:   required from here
/home/yuan/Code/test/src/common.cpp:72:11: error: passing ‘const quat’ as ‘this’ argument discards qualifiers [-fpermissive]
/home/yuan/Code/test/src/common.cpp:25:7: note:   in call to ‘quat quat::Inv()’
  quat Inv()

因此，在我看来，即使我使用typeid进行检查，似乎也无法假定param是“ quat”。我错了吗？ 我可以更改特定类的赋值运算符吗？

这是我第一次问问题。因此，如果我的问题格式有误，请告诉我。谢谢！

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