len() should always return something

[Marcus Wanner]

On 7/25/2009 10:08 AM, Piet van Oostrum wrote:
>>>>>> Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> (SD) wrote:
> 
>> SD> Ambiguity essentially boils down to being unable to reasonably predict 
>> SD> the expectation of the coder. I say "reasonably", because if you allow 
>> SD> unreasonable situations, everything is "ambiguous":
> 
> That's for me the reason that len(42) is ambiguous. The OP apparently
> had 1 as expectation, whereas my first thought was the minimal number of
> bits to represent the number and 7.5 million came later :=). The number
> of bits I certainly find reasonable, and I would find the number of
> decimal digits equally reasonable. More so than 1, actually. 1 as the
> length of an int doesn't give any information.
Well, for my two cents, I will say that the number of binary bits or 
decimal digits is certainly the most sensible return value, and that the 
former is the most useful, because the latter can be got with 
len(str(42)). However, the former can also be (/slightly/ less)easily 
got with len(bin(42))-2...

I also think that "Explicit is better than implicit." says that there 
should be no return value in this case, as any return value would be 
implicit.

Marcus