Uniform Initializer lists in C++11

In my previous article about the latest C++11 standard I talked about automatic type detection and keyword decltype Today I will take another major enhancement in C++11 called the Initializer List or Uniform Initialization Syntax. 

Let us first see the user pain points this feature is trying to resolve :

Till now C++ has multiple ways to initialize objects, for example:

1. The conventional way

    int x = 10;
    std::string str = "mcn";

    int x(10);
    std::string str("mcn");
    int x = int();   // default constructor

    int arr[] = {1,2,3,4,5};
    struct Student
    {
        std::string name;
        int rollno;
    };
    Student a = {"Kamal", 5};

    // Keping struct (and not class) for convenience
    // default members of struct are public.
    struct Student
    {
        std::string name;
        int rollno;
        Student():name(""), rollno(-1){} // default values
        Student(_name, _rollno) : name(_name), rollno(_rollno){}
    };

    int *ptr = new int[10]; // Cannot initialize the array in such cases

    struct MyClass
    {
        MyClass(std::initializer_list);
    };

    MyClass obj  = {1,2,3,4};
    MyClass obj2 = {1,2,3};
    MyClass obj3 = {1};

    class MCN
    {
        int a;
        int b;
        public: MCN(int i, int j); // constructor
    };

    MCN obj {0 , 1}; // Same as MCN obj(0,1);

    int * ptr = new int[5] {1,2,3,4,5};

    struct MCN
    {
        int arr[3];
        MCN() : arr{1,2,3} {}
    };

    std:vector<int> v {1, 2, 3, 4};