[Python-Dev] Re: anonymous blocks

[Guido van Rossum]

> If the iterator fails to re-raise the StopIteration exception (the spec
> only says it should, not that it must) I think the return would be ignored
> but a subsquent exception would then get converted into a return value. I
> think the flag needs reset to avoid this case.

Good catch. I've fixed this in the PEP.

> Also, I wonder whether other exceptions from next() shouldn't be handled a
> bit differently. If BLOCK1 throws an exception, and this causes the
> iterator to also throw an exception then one exception will be lost. I
> think it would be better to propogate the original exception rather than
> the second exception.

I don't think so. It's similar to this case:

    try:
        raise Foo
    except:
        raise Bar

Here, Foo is also lost.

-- 
--Guido van Rossum (home page: http://www.python.org/~guido/)