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  1. #include <iostream>
  2. #include <cassert>
  3. #include <vector>
  4. #include <type_traits>
  5. using namespace std;
  6.  
  7. template<class C>
  8. struct Iterator{
  9.     operator bool() const{
  10.         return startiterator != enditerator;
  11.     }
  12.     const Iterator &operator ++(){
  13.         assert(*this);
  14.         startiterator++;
  15.         return *this;
  16.     }
  17.     const Iterator operator ++(int){
  18.         Iterator other(*this);
  19.         startiterator++;
  20.         return other;
  21.     }
  22.     typename C::iterator startiterator, enditerator;
  23.     //typename C::iterator sollte durch decltype(C::begin()) oder so ersetz werden
  24.     Iterator(C &c) : startiterator(c.begin()), enditerator(c.end()){
  25.     }
  26.  
  27.     auto operator *() -> decltype(*startiterator){
  28.         //hier muss man noch was mit add_const und add_rvalue_reference machen
  29.         return *startiterator;
  30.     }
  31. };
  32.  
  33. //Am ende den ganzen Spaß nochmal für const-Iterator
  34.  
  35. int main(){
  36.     vector<int> v = {42, 37, 128};
  37.     Iterator<vector<int>> it(v); //kann man noch in eine makeIterator-Funktion tun
  38.     while (it){
  39.         cout << *it << ' ';
  40.         it++;
  41.     }
  42. }
Success #stdin #stdout 0s 3428KB
comments (?)
stdin 
Standard input is empty
stdout 
42 37 128
https://ideone.com/Frl33B
language:
C++14 (gcc 8.3)
created:
12 years ago
visibility:
public

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