Question

我的代码中出现了一些错误，我无法弄明白。我将代码缩减为非常基本的简单函数/类调用，但仍然存在问题。

#include <iostream>
using namespace std;

template <class T> 

class FC
{
private: 
    double netprofit, costofinvest;
    double curras, invent, curliab;
public: 

    void ROI(double np, double ci)
    {
     netprofit = np; costofinvest = ci;
    }

    double getROI()
    {
     return (netprofit - costofinvest) / costofinvest;
    }

    void ATR(double ca, double inv, double cl)
    {
     curras = ca; invent = inv; curliab = cl;
    }

    double getATR()
    {
    return (curras - invent) / curliab;
    }

};


int main()
{
 FC ROI, AcidTestRatio; 

 ROI.ROI(27, 288);
 cout << ROI.getROI() << endl;

 AcidTestRatio.ATR(77, 2l, 344);
 cout << AcidTestRatio.getATR() << endl;


return 0;
}

我得到的错误如下：

In function 'int main()':
39:22: error: missing template arguments before 'ROI'
41:2: error: 'ROI' was not declared in this scope
44:2: error: 'AcidTestRatio' was not declared in this scope

Answer 1

你需要给出一个模板参数'T'：

FC<float> ROI, AcidTestRatio;

但正如alain指出的那样，您还没有使用T，所以您也可以改为从代码的开头删除template <class T>。

或者，您可能希望使用T作为成员的类型而不是double：

template <class T> 
class FC
{
private: 
    T netprofit, costofinvest;
    T curras, invent, curliab;
public: 

    void ROI(T np, T ci)
    {
     netprofit = np; costofinvest = ci;
    }

    T getROI()
    {
     return (netprofit - costofinvest) / costofinvest;
    }

    void ATR(T ca, T inv, T cl)
    {
     curras = ca; invent = inv; curliab = cl;
    }

    T getATR()
    {
    return (curras - invent) / curliab;
    }
};

<强>更新： Full example here

我在C ++中的模板代码产生了我似乎无法解决的奇怪错误。

1 个答案: