问题描述
我有一个类模板的问题。我希望类中的私有数据是某种数字类型的向量的向量,即:
I have a problem with a class template. I want the private data in a class to be a vector of vectors of some kind of numeric type, i.e:
std::vector<std::vector<double> >
std::vector<std::vector<std::complex<double> > >
但我想要的矢量类型(我使用的第三方矢量库和stl向量)和要模板化的元素类型。我试过模板模板,但现在我不认为这是我的问题的解决方案。一个高度简化的例子是:
But I want the type of vector (I'm using a library of third party vectors along with stl vectors), and the element type to be templated. I tried template templates but now I don't think that is the solution to my problem. A highly simplified example is:
#include <complex>
#include <vector>
template<typename T>
class Fred {
std::vector<T> data_;
};
int main(){
Fred<std::vector<double> > works;
//Fred<std::vector<std::complex<double> > doesnt_work;
return 0;
}
如图所示,它编译正常,但如果我取消注释main中的第二行,我收到错误(g ++ 4.6):
As shown it compiles fine, but if I uncomment the second line in main, I get the error (g++ 4.6):
error: template argument 1 is invalid
为什么会收到这个错误?任何人都有建议的修复?
谢谢!
Why do I get this error? And does anyone have a suggested fix?Thanks!
推荐答案
#include <complex>
#include <vector>
template<typename T>
class Fred {
std::vector<T> data_;
};
int main(){
//Fred<std::vector<double> > works;
Fred<std::vector<std::complex<double> > > doesnt_work;
return 0;
}
您错过了 doesnt_work
声明中的第三个>
。
Works well. You miss third >
in declaration of doesnt_work
.
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