[Python-ideas] all, any - why no none ?

[Bruce Leban]

If you really mean "if all items in seq are None" then all(x is None for x
in seq) is very clear and explicit that you don't mean  all(x == None for x
in seq) which is not exactly the same thing.

If you don't care about exactly being None and you just want falsenes, then not
any(seq) works already.

If I saw none(seq) I would think it meant "none of seq is true" as that is
a more common phrase. You'd need a name like all_none(seq). But then I want
any_none() and none_none() too. And  all_true() and all_false(), etc. Not
enough value here.

--- Bruce
Follow me: http://www.twitter.com/Vroo http://www.vroospeak.com




On Tue, Apr 10, 2012 at 8:22 AM, Steven Samuel Cole <
steven.samuel.cole at gmail.com> wrote:

> hello,
>
> i'm aware they've been around for quite a while, but for some reason, i
> did not have the builtins all(seq) and any(seq) on the radar thus far. when
> i used them today, i just assumed there was a corresponding none(seq), but
> was surprised to learn that is not true.
>
> why is that ? has this been considered ? discussed ? dismissed ? i did
> search, but the net being neither case-sensitive nor semantic, the results
> were off topic.
>
> sure, i can do not all or not any or any of these:
> http://stackoverflow.com/q/**6518394/217844<http://stackoverflow.com/q/6518394/217844>
> http://stackoverflow.com/q/**3583860/217844<http://stackoverflow.com/q/3583860/217844>
> but none(seq): True if all items in seq are None
> would IMHO be the pythonic way to do this.
>
> what do you think ?
>
> # ssc
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