max(), sum(), next()

Gabriel Genellina gagsl-py2 at
Sun Sep 7 22:13:11 CEST 2008

En Sun, 07 Sep 2008 14:30:09 -0300, Mensanator <mensanator at> escribió:

> Actualy, I already get the behaviour I want. sum([1,None])
> throws an exception. I don't see why sum([]) doesn't throw
> an exception also (I understand that behaviour is by design,
> I'm merely pointing out that the design doesn't cover every
> situation).
> Exactly. That's why I would prefer sum([]) to raise an
> exception instead of giving a false positive.

The built in behavior can't be good for every usage. Nobody prevents you from defining yoru own function tailored to your own specs, like this:

def strict_sum(items):
    items = iter(items)
        first =
    except StopIteration:
        raise ValueError, "strict_sum with empty argument"
    return sum(items, first)

Tweak as needed. Based on other posts I believe your Python skills are enough to write it on your own, so I don't see why you're complaining so hard about the current behavior.

Gabriel Genellina

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