simple newbie question

[Isaac To]

>>>>> "Mike" == Mike Meyer <mwm at mired.org> writes:

    Mike> If you're used to C, it's the difference between: struct Foo v1,
    Mike> v2, *vp1, *vp2;

    Mike> Foo_fill(&v1); v2 = v1; /* 1 */ vp1 = &v1; vp2 = vp1; /* 2 */

    Mike> You now have two Foo's, v1 and v2. vp1 and vp2 both point at
    Mike> v1. Python assignment is like statement #2, *not* statement #1.

Perhaps a better analogy is:

  struct list { ... };
  struct list *v1, *v2;
  v1 = (struct list *)malloc(sizeof(struct list));
  v2 = v1;
  v2 = (struct list *)malloc(sizeof(struct list));

and

  struct list { ... };
  struct list *v1, *v2;
  v1 = (struct list *)malloc(sizeof(struct list));
  v2 = v1;
  listappend(v2, 1);

The easiest way for C people to understand Python variables is to think all
of them as pointers (and there is no pointer to pointer).  Then everything
will be clear again.

Regards,
Isaac.