Paul E.C. Melis wrote:

>Hmmm, according to the Pickaxe book "In general, clone and dup may have
>different semantics in descendent classes. While clone is used to duplicate
>an object, including its internal state, dup typically uses the class of the
>descendent object to create the new instance."
>
>I must say that this doesn't make it clearer for myself either :/
>
Agreed.  There's also the problem that ruby doesn't seem to have a 
deep-copy.  If an object doesn't provide its own deep-copy equivalent, 
internal objects still reference the same object-id's.
a = b.dup
A's objects may have new clone's of b's values, but internal objects may 
still point to the same object-id, so change's to a may affect b.
I'd love to have some help on this one.  It seems like an odd ommision - 
or are classes supposed to impliment a copy-constructor like equivalent 
?  a = AClass.new( b)  ?