On Sun, Mar 15, 2009 at 10:50 AM, Michael Foord <fuzzyman@voidspace.org.uk> wrote:
Brett Cannon wrote:
Without knowing what StatementSkipped is (just some singleton? If so why not just used SkipStatement instance that was raised?) and wondering if we are just going to continue to adding control flow exceptions that directly inherit from BaseException or some ControlFlowException base class, the basic idea seems fine by me.
Note that using exceptions for control flow can be bad for other implementations of Python. For example exceptions on the .NET framework are very expensive. (Although there are workarounds such as not really raising the exception - but they're ugly).
Isn't it better practise for exceptions to be used for exceptional circumstances rather than for control flow?
If my understanding is correct, the primary use case for this is when an exception is raised by an __enter__() method and caught by an enclosing __exit__() method. So at least in that case, you've already incurred the cost of an exception. It might be nice to see an example of this being used with only a single context manager. Is that possible? Steve -- I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a tiny blip on the distant coast of sanity. --- Bucky Katt, Get Fuzzy