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From: Paul Mensonides (pmenso57_at_[hidden])
Date: 2006-01-21 20:21:30

> -----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). Thus, the other productions are for the decimal point (.) and for the
sign (+ or -).

Paul Mensonides

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