小编Aus*_*tin的帖子

我想在列表类中重载迭代器的"+"运算符,类似于

list<double>::iterator operator+(const list<double>::iterator& it, int n)

这很好用.但是,当我尝试将其实现为模板时,就像

template<class T>
typename list<T>::iterator operator+(const typename list<T>::iterator& it, int n)

我收到错误信息,如,

no match for 'operator+' in 'it + small_index'

无法弄清楚原因......

代码附在下面,

#include<iostream>
#include<list>
using namespace std;

template<class T>
ostream& operator<< (ostream& os, const list<T>& l)
{
  typename list<T>::const_iterator i = l.begin();
  for (;i!=--l.end();i++)
    os<<*i<<";";
  os<<*i<<endl;
  return os;
}

template<class T> //this is where it goes WRONG.
                  //If don't use template, delete "typename", T->double, runs well
typename list<T>::iterator operator+(const typename list<T>::iterator& it, int …