Why Python does *SLICING* the way it does??

[Antoon Pardon]

Op 2005-04-20, Torsten Bronger schreef <bronger at physik.rwth-aachen.de>:
> Hallöchen!
>
> nde at no.spam.org (Nick Efford) writes:
>
>> seberino at spawar.navy.mil <seberino at spawar.navy.mil> wrote:
>>> Many people I know ask why Python does slicing the way it does.....
>>
>>> Can anyone /please/ give me a good defense/justification???
>>
>>> I'm referring to why mystring[:4] gives me elements 0, 1, 2 and 3
>>> but *NOT* mystring[4] (5th element).
>>
>> mystring[:4] can be read as "the first four characters of
>> mystring".  If it included mystring[4], you'd have to read it as
>> "the first five characters of mystring", which wouldn't match the
>> appearance of '4' in the slice.
>>
>> [...]
>>
>> It all makes perfect sense when you look at it this way!
>
> Well, also in my experience every variant has its warts.  You'll
> never avoid the "i+1" or "i-1" expressions in your indices or loops
> (or your mind ;).
>
> It's interesting to muse about a language that starts at "1" for all
> arrays and strings, as some more or less obsolete languages do.  I
> think this is more intuitive, since most people (including
> mathematicians) start counting at "1".  The reason for starting at
> "0" is easier memory address calculation, so nothing for really high
> level languages.

Personnaly I would like to have the choice. Sometimes I prefer to
start at 0, sometimes at 1 and other times at -13 or +7.

-- 
Antoon Pardon