Devanagari int literals [was Re: Should non-security 2.7 bugs be fixed?]

[Rustom Mody]

On Sunday, July 19, 2015 at 12:46:26 PM UTC+5:30, Marko Rauhamaa wrote:
> Chris Angelico:
> 
> > On Sun, Jul 19, 2015 at 2:45 PM, Steven D'Aprano  wrote:
> >> sys.setdigits('Devanagari')
> >
> > Easiest way to play with this would be a sys.displayhook, I think;
> 
> I think the numeral selection is analogous to the number base:

Nice analogy

> 
>    >>> 0o10
>    8
>    >>> "{:o}".format(0o10)
>    '10'
> 
> what we need is:
> 
>    >>> "{:d/base({base})}".format(0o10, base=7)
>    '11'
>    >>> "{:d/numeral('{num}')".format(0o10, num="European")
>    '8'
>    >>> "{:d/numeral('{num}')".format(0o10, num="Roman")
>    'VIII'
>    >>> "{:d/numeral('{num}')".format(0o10, num="RomanLowerCase")
>    'viii'
>    >>> "{:d/numeral('{num}')".format(0o10, num="EasternArabic")
>    '٨'
>    >>> "{:d/numeral('{num}')".format(0o10, num="Devanagari")
>    '८'
> 
> IOW, don't make it global.

But it is willy-nilly global.
Python:
>>> 4+5
9
>>> 

Unix bc:
$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 
4+5
9
obase=8
4+5
11

IOW bc has two (global) variables ibase and obase for input and output base.
If you dont provide these as settable you hardwire them at 10 (8/16 in some
assembly languages)¹

Hopefully you will agree that python is more full-featured than bc and should
subsume bc functionality?

[Implementability is a second question and ease of implementability a third]

I believe numeral-language is similar

---
¹ When Ive played around with writing assemblers for toy machines, the hardwired
10-base has often been a nuisance. Of course one can in principle rebuild an REPL.
Repurposing the existing one is usually a far more palatable option (for me).