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Calling virtual method of base class nested in template class
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Subject: Calling virtual method of base class nested in template class
Date: 28 Aug 2006 18:06:06 -0400
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Hi all.
Here's a little quandry I've run in to and can't tell if it's a compiler
bug, or if it's bad code. First, here's the code:
===================================
#include <stdio.h>
template < typename T >
class B
{
public:
B( ) { }
class N1
{
public:
N1( ) { };
class N2
{
public:
N2( ) { };
virtual void f( )
{
printf( " B< >::N1::N2::f( )\n" );
}
};
};
T _m;
};
class D : public B< int >
{
public:
class N1 : public B< int >::N1
{
public:
N1( ) : B< int >::N1( ) { };
class N2 : public B< int >::N1::N2
{
public:
N2( ) : B< int >::N1::N2( ) { };
virtual void f( )
{
printf( " D::N1::N2::f( )\n" );
( ( B< int >::N1::N2* ) this )->f( );
}
};
};
};
void
main( int argc, char* argv[ ] )
{
D::N1::N2 n2;
n2.f( );
}
==================================
Invoking n2.f( ) causes an infinite loop, dumping out "D::N1::N2::f( )"
ad-nausium. I am trying to call the base-class f( ) in B::N1::N2, but the
compiler just generates code that instead calls D::N1::N2::f( ) recursively.
What am I doning wrong? How can I call the base's f( )?
Thanks for any help you can offer!
- Roger
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