In article <email@example.com>,
Paul Wilson <firstname.lastname@example.org> wrote:
>In article <E9AxB1.7nA@ecf.toronto.edu>,
>Patrick Doyle <email@example.com> wrote:
>>I think if a language has the concept of mutability, then it should also
>>have the concept of object identity because both the cases presented in
>>the previous paragraph are very useful in different curcumstances.
>>Of course if a language has no mutability, then object identity is
>I'm not sure that even the latter is right. It seems to me that it
>can be reasonable to use object identity to represent conceptual-level
>identities, even in purely functional programs.
Can you give an example of two immutable objects, alike in every way,
which need to be distinguished?