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Delegating Constructor in c++ | C++ 11

Delegating Constructor :
In Java, we can one constructor  from another constructor, which is not possible in c++

 class Cat 
{
   public:
   Cat() { ... }
   Cat(int a) { Cat(); doOtherThings(a); }
};
// But in case of C++ 03, we achieve this through creating a new function,

 class Cat
 {
   init() { ... };

    public:
   Cat() { init(); }
   Cat(int a) { init(); doOtherThings(); }
};

// With C++ 11, we can call constructor through an initializer list, also we can perform initialization for class data members.

 class Cat {
   int age = 9;
   public:
   Cat() { ... }
   Cat(int a) : Cat() { doOtherThings(); }
};


Limitation:
Cat() has to be called first.
i.e. The constructor can't be called in middle or at the last in the other constructor.

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