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Re: Proposal
On Fri, Sep 28, 2001 at 12:36:13AM +0100, Neil Booth wrote:
> Frank Klemm wrote:-
>
> > '_' should be allowed in numbers. It is allowed between the digits of
> > numbers in a C/C++ source _before_ preprocessing. It is not allowed between
> > digits which are 'created' during the preprocessor phase.
>
> Why are you so keen to disallow it in created tokens?
>
Write a filter which converts a C_99 source file to C99.
The first with this restriction, the second without.
It must be pssoible to translate such source file with "old" compilers.
> If a patch to implement '_' in numbers were submitted, I would require
> that a preprocessing number be a pp number no matter how it is created;
> I'm pretty sure Zack would agree with me.
>
> > #define MY_MERGE_5(a,b,c,d,e) a##b##c##d##e
> > #define MILLION MY_MERGE_5 ( 1, _, 000, _, 000 )
> > #define BILLION MY_MERGE_5 ( MILLION, _, 000, _, 000 ) // UK notation
>
> BILLION won't expand to what you think. As for UK notation, I'm
> British and I can't think of the last time I've seen a billion have 12
> zeroes. In fact, I think the only time it occurs is when people are
> comparing the claimed British and American forms :-)
>
A billion has no zeros: 1.e+12
--
Frank Klemm