[Python-checkins] cpython: Issue #12040: Expose a new attribute `sentinel` on instances of

[Antoine Pitrou]

On Tue, 7 Jun 2011 12:47:37 +1000
Nick Coghlan <ncoghlan at gmail.com> wrote:
> 
> We should probably follow this model for threading.Thread.ident as
> well (i.e. throwing an exception rather than returning None if the
> thread hasn't been started yet).

Well, Process.ident returns None as well ;)

> Also, for runtime state errors, we tend to use RuntimeError rather
> than ValueError (e.g. see the errors thrown by
> contextlib._GeneratorContextManager)

Well, it depends. For example, closed files raise a ValueError when you
try to do operations on them. I tend to think of RuntimeError as
something that happens without any clear responsibility from the user,
although that's debatable (recursion errors can occur because of a
programming bug, but also simply because a structure is nested much too
deeply).

Of course, current coding practice in other multiprocessing.Process
methods and properties doesn't help, since it uses asserts to guard
against misuse!

Regards

Antoine.