Re: forward declaration of class from another namespace
Sergey Lukoshkin wrote:
Hello, dear community!
I've faced such a problem:
1. I got header "headerA.h" with the following code:
----------------------------------------
#include "headerB.h"
namespace A
{
class A
{
public:
create_b_ojects()
{
B* pB = new B( this );
Here you probably meant:
B::B* pB = new B::B( this );
Otherwise, the compiler would not be able to locate class B.
}
};
}
-------------------------------------
2. And I got header "headerB.h" with the following code:
-------------------------------------------
namespace B
{
class B
{
public:
B(){}
B( /* here I need to use pointer to object of type A::A
*/ ){....}
};
}
-------------------------------------------
Question:
what is the correct way to make forward declaration of class A::A in
module B?
Add this before the line 'namespace B':
<code>
namespace A
{
class A;
}
</code>
Namespaces have the very nice property that you can re-open them. In
other words, you can have multiple namespace definitions with the same
(non-empty) name, and the compiler will automatically merge all those
definitions.
Thanks in advance!!
Bart v Ingen Schenau
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