Re: \xDD patch for 7.5devel

On Thu, 6 Nov 2003, Jason Godden wrote:

> On Thu, 6 Nov 2003 06:25 am, Markus Bertheau wrote:
> > В Срд, 05.11.2003, в 16:25, Tom Lane пишет:
> > > > +#define HEXVALUE(c) (((c)>='a') ? ((c)-87) : (((c)>='A') ? ((c)-55) :
> > > > ((c)-'0')))
> > >
> > > This seems excessively dependent on the assumption that the character
> > > set is ASCII.  Why have you hard-coded numeric equivalents into this
> > > macro?
> >
> > What not ASCII compatible character sets are out there in use still
> > today?
>
> Ah, yes - didn't even think about the character sets.  If thats the case then
> octal needs attention as well because it makes a similar assumption.  Peter

I haven't looked at the code in question, but assuming the digits are
contiguous and in order is safe, the C spec mandates that.  Assuming that
the letters are in order and contiguous is not safe.