Re: [boost] [wave] pp-number bug?

From: Edward Diener (eddielee_at_[hidden])
Date: 2006-01-21 21:32:42

Paul Mensonides wrote:
>> -----Original Message-----
>> From: boost-bounces_at_[hidden] 
>> [mailto:boost-bounces_at_[hidden]] On Behalf Of Edward Diener
> 
>> I have never understood the definition of a pp-number in the 
>> C++ standard. I am using the 1998 version and I read:
>>
>> ppnumber:
>>           digit
>>           . digit
>>           ppnumber digit
>>           ppnumber nondigit
>>           ppnumber e sign
>>           ppnumber E sign
>>           ppnumber .
>>
>> Since "ppnumber digit" and "ppnumber nondigit" covers all 
>> sequences beginning either with a "digit" or a ".digit" 
>> followed by anything else which is not a whitespace character 
>> or a comment, why specify the last three items ?
> 
> Despite the name, 'nondigit' is not any non-digit character.  It is just the
> alphabetic characters, the underscore, and universal character names (subject to
> annex E). 

Thanks, I see it now. The definition of non-digit ( and digit ) 
unfortunately was made not in Preprocessing Numbers section, where it 
was first mentioned, but in the Identifiers section. Thanks for pointing 
this out to me.