Use of Pointer Addresses to compare Class Instances

[henning]

Hey,

I would like to know whether it is good practice to use Pointer addresses to check whether two class instances are the same. E.g.:

Foo x;

Foo *p1 = &x;
Foo *p2 = &x;

if (p1 == p2) std::cout << "Same instance";

Can this get me into trouble at some point or are pointer addresses in fact completely static during runtime? I need this to find elements in a list for example.

Thanks for any help!

Best,
Henning

[Athar]

It's safe, the address of an object never changes after it has been created.

[henning]

Great - thx Athar!

[moorecm]

This was commonly done in assignment operators to prevent assignment to ones self. Modern approaches use the copy and swap idiom for exception safety.