Re: [boost] [wave] resetting input stream during the lifetime of awave::context

From: Hartmut Kaiser (hartmut.kaiser_at_[hidden])
Date: 2007-03-11 10:22:57

Stefan, 

> >> Does anything like this exist ? Are there plans to support 
> such use 
> >> cases ?
> > 
> > Wave does already support that! The iterator returned from 
> the context 
> > has a member function force_include():
> > 
> >     context_type::iterator_type it = ctx.begin();
> >     for (each of the files to be pre-included)
> >         it.force_include(filename, last_name);
> 
> Excellent ! Unfortunately it seems the context::iterator_type 
> isn't documented anywhere, at least I couldn't find this 
> feature in 
> http://boost.org/libs/wave/doc/class_reference_context.html.

You're right. It's not documented anywhere, I'll have to add this info.

> Also, I believe the implementation contains a bug (though to 
> be really sure I'd need to see the specification):
> 
> It appears the force-included header is searched as if 
> included by means of #include "file", i.e. starting in the 
> directory containing the main input.
> 
> In contrast, the gcc documentation explains that the search 
> should disregard that main input's directory, and start 
> searching in the current working directory instead 
> (http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Preprocessor-Opti
ons.html#Preprocessor-Options).
> 
> (Please bear with me for using gcc as the authoritative input ;-) )

You're right again. The filename is interpreted as if it has been specified
by a #include "file" directive. Frankly, I didn't even look at the gcc
behavior wrt this. I'm not sure about the rationale of gcc's behavior
either, I chose Wave's behavior as to allow for (force-)include files in the
directory containing the main file.

Do you think we should change that behavior? 

Regards Hartmut

> 
> Thanks a lot !
> 
> 		Stefan
> 
> -- 
> 
>       ...ich hab' noch einen Koffer in Berlin...
> _______________________________________________
> Unsubscribe & other changes: 
> http://lists.boost.org/mailman/listinfo.cgi/boost