constructor???

I found this code in a book.

Code:

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class Binary_Search_Tree{
    struct Node;
    Node * _root;
    //blah
    //blah
};

struct Binary_Search_Tree::Node{
    Type _;
    Node* _left;
    Node* _right;
    Node(Type = Type(), Node* =0, Node* = 0);
};

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1.)What does that line mean? Is it a constructor for 'struct's'?
I've never heard of constructors for structs.
2.)More over throughout the whole program, I dont see any

Code:

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template<class Type>

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Is it correct?

'Type' better be a typedef or class somewhere. The logical choice would've been to make it a template parameter as you suggested, but apparently, they didn't do that.

Structs can have constructors, destructors, private member data, virtual functions, inherit from one another, etc.

The only difference between classes and structs is their default access. That is:

Code:

---

struct foo1 {
  int bar; // This is public
};

class foo2 {
  int bar; // This is private
};

---

That is the only difference.

Minor clarification: these are the only differences:

Code:

---

struct foo1 : base { // base is inherited publicly
  int bar; // This is public
};
 
class foo2 : base { // base is inherited privately
  int bar; // This is private
};

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Right... Thanks.

I always explicitly state public/private inheritance, and never think about it.

Cheers

cool... I never knew this...

Quote:

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Structs can have constructors, destructors, private member data, virtual functions, inherit from one another, etc.

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