Re: const version of a function w/o copy/paste
On 22 Jul., 14:33, "Gernot Frisch" <m...@privacy.net> wrote:
Hi,
// how can I
const int* GetPInt()const
{
return (const int*)the_non_const_function_using_the_same_name();
}
We had a similar topic quite recently (http://groups.google.de/group/
comp.lang.c++/browse_frm/thread/7943a399a96324bf#), and came up with
the following class:
// Wrapper for plain pointers that behaves as const-correct
// accessor.
template<class t_Class>
class ConstCorrectAccessor
{
t_Class* m_InternalPointer;
public:
ConstCorrectAccessor (t_Class* Pointer)
: m_InternalPointer (Pointer)
{}
// Accessor methods with const-correct overload.
const t_Class* operator-> () const {return m_InternalPointer;}
t_Class* operator ->() {return m_InternalPointer;}
};
class SomeClass
{
public:
void foo () const {}
void bar () {}
};
class AnotherClass
{
public:
ConstCorrectAccessor<SomeClass> SomeObject;
public:
AnotherClass (SomeClass* Object)
: SomeObject (Object)
{}
void foo () const
{
SomeObject->foo (); // OK
SomeObject->bar (); // Error: Non-const method on SomeObject.
}
};
int main ()
{
SomeClass a;
const AnotherClass b (&a);
b.SomeObject->foo (); // OK
b.SomeObject->bar (); // Compilation error: b is const
AnotherClass c (&a);
c.SomeObject->foo (); // OK
c.SomeObject->bar (); // OK: c is not const
}
Regards,
Stuart