Re: Can't access private struct of a class from a friend class

From:
"=?iso-8859-1?q?Daniel_Kr=FCgler?=" <daniel.kruegler@googlemail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Thu, 29 Mar 2007 01:27:18 CST
Message-ID:
<1175145323.525230.275340@e65g2000hsc.googlegroups.com>
jpitt42@gmail.com schrieb:

I get "error: `struct Addr::ADDR_T' is private" from the following
code when trying to access Addr::ADDR_T from MsgFactory, which is a
friend. I have verified that MsgFactory can access private member
data of Addr with no problem, but it's unable to access the struct for
some reason.


I strongly recommend that you always try to post a complete
and/or self-explaining snippet to demonstrate your problem.

class Addr
{
     friend class MsgFactory;

private:
     typedef struct
     {
         int addr;
     } ADDR_T;

...
};


Where is the below accessed getRefAddrStruct() function declared?
I assumed the following scenario:

class Addr
{
      friend class MsgFactory;

private:
      typedef struct
      {
          int addr;
      } ADDR_T;

      const ADDR_T& getRefAddrStruct() const {
         ....
      }
};

Have you considered that getRefAddrStruct() might
be written const-incorrect? You *need* the const
qualifier!

class MsgFactory
{
public:
     boolean
     send(void** ptrPtrMsg, const Addr& refDestAddr);


What is "boolean"? I assume, that it is a typedef equivalent
to bool.

boolean
MsgFactory::send(void** ptrPtrMsg, const Addr& refDestAddr)
{

// The following line causes "error: `struct Addr::ADDR_T' is private"

     printf("Hidden address = %d",
refDestAddr.getRefAddrStruct().addr);

....
};


I have - of course - the same problem with "boolean" here.
But under the premisse that my assumed code applies
here, I see no problem with your code and it should compile.

Greetings from Bremen,

Daniel Kr?gler

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