[Pythonmac-SIG] (no subject)

[Keith Nemitz]

>>
>>
>> huh? I mean does everyone use[-3:] instead and 0 is taboo? I'm used 
>> to the Icon programming language where "food"[-3:0] returns --> ood
>
> "food"[-3:] is equivalent to "food"[-3:None] (that is, literally, how 
> it works out internally)
>
> "food"[-3:0] is just backwards :)  If anything, it should give you 
> "oof", but that's too confusing.
>
> -bob
>
Thank you. I knew there had to be a reason. If you think about lists as 
ring buffers, however, then  "food"[-3:0]-->"ood"  makes plenty of 
sense and can be very useful. My case that started this whole thread 
had to do with iterating from negative to positive, returning larger 
substrings on each iteration. It broke with the zero index. So I had to 
special case it.

sigh,  I wonder if adding this 'concept' to python (indexing lists as 
ring buffers) would break any existing code...

Heck while I'm at it, changing the language, might as well add nested 
comments, and (my personal favorite) record names, implemented like 
this:

record <tuple of enums>
tuple of enums ::= (<enum> [,enum]*)
enum ::= <string>[= <int>]

...such that the keyword 'record' turns the strings into module and/or 
class scoped indexes.


Isn't it fun to dream?

Keith Nemitz