this is my code:
#include<stdarg.h>
#include<deque>
using namespace std;
template<typename T,int dim>
class trj:public deque<T>{
public:
void push_back(T,...);
virtual void set_calculate_method(int)=0;
};
template<typename T,int dim>
class bb:public trj<T,dim>{
public:
void set_calculate_method(int);
};
template<typename T,int dim>
void trj<T,dim>::push_back(T in,...){
va_list ap;
T aux;
va_sta开发者_运维百科rt(ap,in);
aux=in;
deque<T>::push_back(new T[dim]);
for(int i=0;i<dim;i++){
*(deque<T>::back()+i)=aux;
aux=va_arg(ap,T);
}
va_end(ap);
}
int main(){
bb<double,3> t;
t.push_back(2,3,4);
return 0;
}
and i have this compiler error
uno.cpp: In member function ‘void trj<T, dim>::push_back(T, ...) [with T = double, int dim = 3]’:
uno.cpp:57: instantiated from here
uno.cpp:16: error: no matching function for call to ‘trj< double, 3 >::push_back(double*)’
/usr/include/c++/4.4/bits/stl_deque.h:1201: note: candidates are: void std::deque <_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = double, _Alloc = std::allocator<double>]
uno.cpp:57: instantiated from here
uno.cpp:18: error: invalid type argument of ‘unary *’
Why does the compiler emit " uno.cpp:16: error: no matching function for call to ‘trj< double, 3>::push_back(double*)" if i wrote "deque< T>::push_back(new T[dim]); " in that line?
Because deque<T>::push_back
is expecting a const reference and you are passing a non-const pointer.
I can't be sure but I think you are just wanting to do a deque<T>::resize
and pass in dim
.
deque<T>::push_back
wants T
, not array of T
s.
By the way, I would strongly discourage deriving from deque
, as its destructor is non-virtual. If some code deletes an instance of your class by a pointer to the base class, you'll get undefined behaviour.
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