Writing a string.ishex function

[Duncan Booth]

MRAB <python at mrabarnett.plus.com> wrote:

> Duncan Booth wrote:
>> MRAB <python at mrabarnett.plus.com> wrote:
>> 
>>> I raise you one character:
>>>
>>> ishex2 = lambda s: not(set(s)-set(string.hexdigits))     # Yours
>>> ishex3 = lambda s: not set(s)-set(string.hexdigits)      # Mine
>>>
>>> I could actually go three better:
>>>
>>> ishex3=lambda s:not set(s)-set(string.hexdigits)
>> 
>> But none of those pass your own "ishex('') should return False" test.
> 
> Neither do the others!

That's true, but since you were the one that pointed out they were all 
broken I would have thought your solution should actually work.

I'm sure you'll agree that a longer solution that works trumps any short 
but broken solution.