Below is a condensed version of my code that gives me a compiler error. The compiler tells me to put typename in front of 'std::deque::reverse_iterator', which makes sense. But if I do I receive the error at the bottom. What does it mean? How can it be resolved?
#include <iostream>
#include <deque>
template<class T>
class Stack{
public:
Stack(){}
~Stack(){}
void push(T c) { s.push_back(c); }
void inspect() const{
for(typename std::deque<T>::reverse_iterator i=s.rbegin(); i!=s.rend(); i++)
std::cout << *i << std::endl;
}
private:
typename std::deque<T> s;
};
int main(){
Stack<int> s;
s.push(1);
s.inspect();
return 0;
}
Error:
error: no matching function for call to 'std::_Deque_iterator<int, int&, int*>::_Deque_iterator(std::reverse_iterator<std::_Deque_iterator<int, const int&, const int*> >::iterator_type)'|
note: candidates are:|
note: std::_Deque_iterator<_Tp, _Ref, _Ptr>::_Deque_iterator(const iterator&) [with _Tp = int; _Ref = int&; _Ptr = int*; std::_Deque_iterator<_Tp, _Ref, _Ptr>::iterator = std::_Deque_iterator<int, int&, int*>]|
note: no known conversion for argument 1 from 'std::reverse_iterator<std::_Deque_iterator<int, const int&, const int*> >::iterator_type {aka std::_Deque_iterator<int, const int&, const int*>}' to 'const iterator& {aka const std::_Deque_iterator<int, int&, int*>&}'|
note: std::_Deque_iterator<_Tp, _Ref, _Ptr>::_Deque_iterator() [with _Tp = int; _Ref = int&; _Ptr = int*]|
note: candidate expects 0 arguments, 1 provided|
note: std::_Deque_iterator<_Tp, _Ref, _Ptr>::_Deque_iterator(_Tp*, std::_Deque_iterator<_Tp, _Ref, _Ptr>::_Map_pointer) [with _Tp = int; _Ref = int&; _Ptr = int*; std::_Deque_iterator<_Tp, _Ref, _Ptr>::_Map_pointer = int**]|
note: candidate expects 2 arguments, 1 provided|
This is a good example of where using auto
would help you more than just saving typing. You're in a const
member function, but trying to use your data member's reverse_iterator
, not const_reverse_iterator
.
Change typename std::deque<T>::reverse_iterator
to typename std::deque<T>::const_reverse_iterator
, or, more simply, auto
.
This is in addition to the extra typename
on your data member.