On Dec 13, 6:49 am, "Tim Rowe" <digi...@gmail.com> wrote: > 2008/12/12 John Machin <sjmac...@lexicon.net>: >
> > (4) in practice, the "default" action would not be "return 0.0"; > > perhaps something along these lines: > > > if balance < -overdraft_limit: > > raise Exception(...) > > That's more likely to be in the withdrawal routine You'd certainly hope that this test would appear in the withdrawal routine. > (and is probably > best not handled as an exception, because it's pretty much normal > flow). If a bank provided a service such as the one implemented by > this program, there'd be no need for it to know about overdraft limits > because it's not making actual transactions. Why would they increase > coupling unneccesarily? Yeah, you're right, much easier to return 0% interest on a negative balance [customers happy; no wear and tear on the call centre] and hope that anomalies are checked somewhere else *and* that somebody #1 is tasked with actioning the anomaly reports and that somebody #2 is keeping an eye on somebody #1. -- http://mail.python.org/mailman/listinfo/python-list