[Python-Dev] What's the status of PEP 505: None-aware operators? (original) (raw)

Michel Desmoulin desmoulinmichel at gmail.com
Tue Dec 12 03:39:17 EST 2017

Le 29/11/2017 à 19:02, Barry Warsaw a écrit :

On Nov 29, 2017, at 12:40, David Mertz <mertz at gnosis.cx> wrote:

I think some syntax could be possible to only "catch" some exceptions and let others propagate. Maybe:

val = name.strip()[4:].upper() except (AttributeError, KeyError): -1 I don't really like throwing a colon in an expression though. Perhaps some other word or symbol could work instead. How does this read: val = name.strip()[4:].upper() except -1 in (AttributeError, KeyError) I don’t know whether I like any of this but I think a more natural spelling would be: val = name.strip()[4:].upper() except (AttributeError, KeyError) as -1 which could devolve into: val = name.strip()[4:].upper() except KeyError as -1 or: val = name.strip()[4:].upper() except KeyError # Implicit as None I would not add any spelling for an explicit bare-except equivalent. You would have to write: val = name.strip()[4:].upper() except Exception as -1 Cheers, -Barry

I really like this one. It's way more general. I can see a use for IndexError as well (lists don't have the dict.get() method).

Also I would prefer not to use "as" this way. In the context of an exception, "as" already binds the exception to a variable so it's confusing.

What about:

val = name.strip()[4:].upper() except Exception: -1

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