Enabling Range-Based For Loops for Custom Containers

To enable range-based for loops for your custom container in C++, you need to define begin() and end() methods that return iterators. These methods allow the compiler to iterate over the elements of your container using a range-based for loop.

Here’s how you can implement it for a custom Party container:

1#include <iostream>
2#include <string>
3#include <stdexcept>
4
5class Player {
6public:
7  std::string Name;
8};
9
10class Party {
11public:
12  Party(Player A, Player B, Player C)
13    : A{A}, B{B}, C{C} {}
14
15  Player A, B, C;
16  
Iterator Class|Show
17  class Iterator{/*...*/};
54
55  Iterator begin() { return Iterator(this, 0); }
56  Iterator end() { return Iterator(this, 3); }
57};
58
59int main() {
60  Party party{Player{"Anna"},
61    Player{"Bob"}, Player{"Cara"}};
62
63  for (Player& p : party) {
64    std::cout << p.Name << ", ";
65  }
66}

1Anna, Bob, Cara,

Explanation

• Iterator Class: Defines the custom iterator with necessary operators like *, ++, ==, and !=.
• begin() and end() Methods: Return instances of the Iterator class. The begin() method returns an iterator pointing to the first element, and the end() method returns an iterator pointing past the last element.
• Range-Based For Loop: The main function demonstrates the range-based for loop, which iterates over the Player objects in the Party container.

By implementing these methods, you enable the use of range-based for loops with your custom container, making your code more intuitive and easier to read.