Re: Adding functions to generic package

[Matthew Heaney <matthewjheaney@earthlink.net>]

Marius Amado Alves <amado.alves@netcabo.pt> writes:

> Is "exchanging values" not "manipulating the container?"

No.  Exchanging values implies that you're manipulating elements in the
container without changing the container object itself.

In the case of a list, the "container object itself" is a record
comprising pointers to the head and foot of the internal linked list,
and the number of elements.

When you "manipulate the container object itself," that means you're
changing the value of a head or foot pointer, or changing the length.  

That's why operation Swap_Links passes the container, since the head or
foot can change.

Swap does not pass the container, since it only exchanges element
values.  It doesn't manipulate the actual container object.

-Matt