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[Python-ideas] a in x or in y

Ethan Furman ethan at stoneleaf.us
Fri Feb 14 01:52:59 CET 2014 
On 02/13/2014 03:32 PM, Haoyi Li wrote:
> Carl Meyer wrote:
>> This makes me think of
>>
>>      X in any(Y, Z)
>
> It also doesn't have the desired laziness, unless we special case *any* in the interpreter, or provide a more generic
> mechanism for lazy parameters without writing *lambda: *everywhere

Well, currently any() and all() return True/False.

To overload like this would require returning an object with a __contains__ like Greg's either() (which is lazy), and a 
__bool__ that does what any() and all() currently do.

I can see it being confusing, and it also doesn't get the chained comparisons like "or in" and friends do.

--
~Ethan~
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