我正在编译以下代码,并且收到错误消息。我想练习中提升模板,我不知道如何来处理这个问题致命错误LNK1120:1个未解决的外部问题
#include <stdafx.h>
#include <iostream>
#include <string>
#include <boost/function.hpp>
#include <boost/array.hpp>
using namespace std;
template<typename R,typename D>
class GenericFunction
{
private:
boost::function<R (D)> f;
protected:
GenericFunction();
public:
GenericFunction(const boost::function<R (D)>& myFunction);
R evaluate(const D& value) const ;
R operator()(const D& value) const;
};
template <typename R, typename D, int N>
class ScalarValuedFunction:public GenericFunction<R,boost::array<D, N>>
{
public:
ScalarValuedFunction(const boost::function<R (const boost::array<D, N>)> &myF);
};
template<typename Numeric, std::size_t N>
Numeric Norm(const boost::array<Numeric , N>& Vec)
{
Numeric Result=Vec[0]*Vec[0];
for (std::size_t i=1; i<Vec.size();i++)
{
Result+=Vec[i]*Vec[i];
}
return Result;
}
int main()
{
const int N=4;
boost::array<double, N> arr={0.2,.3,1.1,4};
ScalarValuedFunction<double, double, N> myfun(Norm<double,N>);
}
和接收以下错误,
ConsoleApplication2.obj : error LNK2019: unresolved external symbol "public: __thiscall ScalarValuedFunction<double,double,4>::ScalarValuedFunction<double,double,4>(class boost::function<double __cdecl(class boost::array<double,4>)> const &)" ([email protected][email protected]@[email protected][email protected][email protected][email protected]@@@[email protected]@@@Z) referenced in function _main
1>c:\users\university\documents\visual studio 2012\Projects\ConsoleApplication2\Debug\ConsoleApplication2.exe : fatal error LNK1120: 1 unresolved externals
请谁能告诉我什么是错我的代码?
您为'ScalarValuedFunction <>'声明了一个构造函数,但没有定义它。当然,一旦你这样做了,你还需要为'GenericFunction <>'定义构造函数。 – ildjarn 2013-02-21 01:57:52