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

From: Hartmut Kaiser (hartmut.kaiser_at_[hidden])
Date: 2006-01-22 22:54:33

> Alberto Ganesh Barbati wrote:
> 
> > However, if run into Wave, the program above produces the error 
> > message:
> > 
> > error: pasting the following two tokens does not give a valid 
> > preprocessing token: "e" and "-"
> > 
> > Who's right? I'd agree with Paul Mensonides, because "1e" 
> is a valid 
> > pp token which is to be formed before applying the ## 
> operator. But my 
> > understanding is quite limited in this area so I commit 
> myself to the 
> > Gurus.
> 
> Paul is right and Wave is wrong. That's a known issue with 
> Wave, it stems from the fact that Wave currently works on C++ 
> tokens, not pp-tokens as mandated by the Standard. This will 
> be fixed in the future, when I change Wave to operate on 
> pp-tokens, rescanning these into C++ tokens after 
> preprocessing. If you need to preprocess this kind of 
> constructs with Wave, you may want to use the --variadics 
> command line option, allowing concatenation of unrelated tokens.

Wave now correctly recognizes pp-number tokens, which get converted to C++
tokens just before they get returned to the calling application. This fixes
a couple of known Wave preprocessing problems (I even enabled a couple of
additional tests failing so far).

Regards Hartmut