Associative Chains in C++
By Phillip Bruce, February 01, 2006
Phillip gets around some of the limitations of the pointer-to-member with a model of class associations that he calls "Associative Chains."
February, 2006: Associative Chains in C++
Listing 4
(a)
template<class Src, class Dst>
class Member_Link : public Typed_Link<Src, Dst>
{
Dst Src::*mptr;
public:
Member_Link(Dst Src::*_mptr) : mptr(_mptr)
{}
Dst &traverse(Src &s)
{
return s.*mptr;
}
// ...
};
(b)
template<class Src, class Dst, class Get =
Dst &(Src::*)(void) const>
class Get_Link : public Typed_Link<Src, Dst>
{
Get get;
public:
Dst &traverse(Src &s)
{
return (s.*get)();
}
// ...
};
(c)
template<class Src, class Dst>
class Array_Link : public Typed_Link<Src, Dst>
{
unsigned int index;
public:
Dst &traverse(Src &id)
{
if (index >= sizeof(Src)/sizeof(Dst)) {
throw Clank(id);
}
return id[Index];
}
// ...
};
