Hi All,
I fail to compile the following code (well, not exactly that code...):
class BB
{
};
class B
{
public:
static B* Create(int i);
};
class D0 : public BB, B
{
};
class D1 : public BB, B
{
};
B* B::Create(int i)
{
if (i == 0)
return new D0();
else
return new D1();
}
int main()
{
B *b = B::Create(1);
delete b;
return 0;
}
And get: "error: 'B' is an inaccessible base of 'D0', 'B'
is an inaccessible base of 'D1' "
But when I change the order of inheritance: "class D0 : public B, BB",
everything works fine.
Why?
TID, Yuval. 2 47383
<yu*****@gmail. com> wrote in message
news:11******** **************@ o13g2000cwo.goo glegroups.com Hi All, I fail to compile the following code (well, not exactly that code...):
class BB { };
class B { public: static B* Create(int i); };
class D0 : public BB, B { };
class D1 : public BB, B { };
B* B::Create(int i) { if (i == 0) return new D0(); else return new D1(); }
int main() { B *b = B::Create(1); delete b; return 0; }
And get: "error: 'B' is an inaccessible base of 'D0', 'B' is an inaccessible base of 'D1' " But when I change the order of inheritance: "class D0 : public B, BB", everything works fine. Why?
TID, Yuval.
You are apparently assuming that access qualifiers like
public BB, B
work in the same way as variable declarations, e.g.,
int x, y
i.e., that they continue in effect for identifiers after the first. They
don't. The access qualifier only has effect on the class that immediately
follows. If you omit a declaration, then you get the default access, which
is private in this case. Do it this way:
class D0 : public BB, public B
{
};
class D1 : public BB, public B
{
};
--
John Carson
On 25 Dec 2005 22:16:51 -0800, yu*****@gmail.c om wrote: Hi All, I fail to compile the following code (well, not exactly that code...):
class BB { };
class B { public: static B* Create(int i); };
class D0 : public BB, B
This is equivalent to class D0: public BB, private B{ };
class D1 : public BB, B { };
B* B::Create(int i) { if (i == 0) return new D0(); else return new D1(); }
int main() { B *b = B::Create(1); delete b; return 0; }
And get: "error: 'B' is an inaccessible base of 'D0', 'B' is an inaccessible base of 'D1' " But when I change the order of inheritance: "class D0 : public B, BB",
This is equivalent to class D0: public B, private BB
everything works fine. Why?
TID, Yuval.
Regards,
-- Zar This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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