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Initializer list in C++

C++ 11 Initializer :

 // C++ 03
class Dog {     // Aggregate class or struct
   public:
      int age;
      string name;
};

 Dog d1 = {5, "Henry"};   // Aggregate Initialization



// C++ 11 Initializer extended the scope of curly brace initialization.

 class Dog
 {
   public:
      Dog(int age, string name) {...};
};

 Dog d1 = {5, "Henry"}; 


/* Uniform Initialization Search Order:
 * 1. Initializer_list constructor
 * 2. Regular constructor that takes the appropriate parameters.
 * 3. Aggregate initializer.
 */

 Dog d1{3};

 class Dog 
{
   public:
   int age;                                // 3rd choice

    Dog(int a) 
   {                            // 2nd choice
      age = a;
   }

    Dog(const initializer_list& vec)  { // 1st choice
      age = *(vec.begin());      
   }
};
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