What's the value of "None" between 2.1.1 and 1.5.2

Steve Holden sholden at holdenweb.com
Fri Nov 30 18:13:28 CET 2001

"Michael Abbott" <michael at rcp.co.uk> wrote ...
> "Steve Holden" <sholden at holdenweb.com> wrote :
> >> So why don't comparisons of this type generate an exception?
> >
> > Because comparisons are used in sorts, for example, and it wasn't
> > considered helpful for sorts of lists of arbitrary datatypes to raise
> > errors.
> Sigh.  I understand.
> Of course, if you are sorting a list of arbitrary datatypes using random
> datatypes as the key then you're in a state of sin.
> I'm trying to figure out how to avoid this sinfulness (in general) in
> Python, but it's not easy!

Maybe. But for your existing simulation, where you seem to be using None to
record "No Value" (?) you can get away with

    something = min([x for x in a if x])

List comprehensions were new in 2.0 (I think), and although they could be
faster in execution they are VERY cool for source code reduction.


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