[Python-ideas] Negative hexes

[MRAB]

On 04/12/2011 01:17, Guido van Rossum wrote:
> On Sat, Dec 3, 2011 at 5:13 PM, Nick Coghlan <ncoghlan at gmail.com
> <mailto:ncoghlan at gmail.com>> wrote:
>
>     On Sun, Dec 4, 2011 at 3:07 AM, Antoine Pitrou <solipsis at pitrou.net
>     <mailto:solipsis at pitrou.net>> wrote:
>      >> This is because Python's integers are not limited to 32 bits or
>     64 bits. If
>      >> you read PEP 237, you'll see that this was one of the hardest
>     differences
>      >> between ints and longs to be resolved. You'd have to include an
>     infinite
>      >> number of leading 'F' characters to format a negative long this
>     way...
>      >
>      > That's a fair point :)
>
>     Random thought... could we use the integer precision field to fix
>     *that*, by having it indicate the intended number of bytes in the
>     integer?
>
>     That is, currently:
>
>      >>> "{:.4x}".format(31)
>     Traceback (most recent call last):
>       File "<stdin>", line 1, in <module>
>     ValueError: Precision not allowed in integer format specifier
>
>     What if instead that produced:
>
>      >>> "{:.4X}".format(31)
>     0000001F
>      >>> "{:.4X}".format(-31)
>     FFFFFFE1
>
> Usually that field is measured in characters/digits, so this should
> probably produce FFE1; you'd need {:.8X} to produce FFFFFFE1. This would
> then logically extend to binary and octal, in each case measuring
> characters/digits in the indicated base.
>
+1

Not only would that be more consistent, it would also have a use-case.