🚀 go-pugleaf

Eric Simon wrote:
> 
> I have a base class, called Animal, and a derived class, called Cat.
> 
> In my main program I have:
> 
> 1.    Animal *p;
> 2.    Cat a(args);
> 3.    p = &a;
> 
> Now, if I define
>     class Cat:Animal{...
> 
> then I get the error in line 3:
>   Can not convert Cat * to Animal *
> 
> But if I define
>    class Cat:public Animal{...
> 
> everything is fine.
> 
> Can anyone tell me why?
> 	[clip]

The default access for classes is private.
p = &a; 	// asks for an implicit conversion.

"Pointers and references to derived classes can be implicitly converted to
pointers and references 
to their base classes if there is an accessible, unambiguous base class."

Key word in this case is accessible (i.e., at least, not private.)

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