cascading python executions only if return code is 0

[Roy Smith]

In article <mailman.4653.1388121800.18130.python-list at python.org>,
 Chris Angelico <rosuav at gmail.com> wrote:

> On Fri, Dec 27, 2013 at 4:05 PM, Roy Smith <roy at panix.com> wrote:
> > There's lists like that for names and genders too.  As in, what do you
> > mean there are people who don't have exactly two names and one gender?
> 
> And addresses, too. The only way to reliably query the user for an
> address is with a single field in which s/he may type anything at
> all... and that freedom includes the possibility of making a right
> hash of it and having delivery fail.
> 
> ChrisA

You're assuming people *have* addresses.

A bunch of years ago (I'm probably dating myself), there was a legal 
ruling in New York that having an address was not a requirement to 
register to vote.  The case in question had to do with a homeless person 
who was refused registration because he didn't have an address.