[Boost-users] [Boost.Wave] util::file_position<> and asserted !is_escaped_lit(..) requirement

Subject: [Boost-users] [Boost.Wave] util::file_position<> and asserted !is_escaped_lit(..) requirement
From: Pekka Seppänen (pekka.seppanen_at_[hidden])
Date: 2011-08-12 09:44:26

Hello.

(Using namespace boost::wave here on.)

It seems that util::file_position<> has an assertion that checks if a given
filename contains any following sequences: <\\>, <\"> or <\?> (using
util::debug::is_escaped_lit).

I wonder why file_position<> does need to check this and if it's so crucial
why it's done using a mere BOOST_ASSERT?

Now, here's comes the reason why I'm asking this: At least with MSVC9's remote
debugger (or some other lowlevel component; not really the interesting part
here) translates all network shares on a remote computer to UNC-paths. This is
correct behaviour and actually a very neat feature. However, as you might be
already aware at this point this leads to the actual problem: Any UNC-path
triggers (consider <\\foo\path\file>) the assertion and things go boom.

It is not possible to easily work around this by refactoring user code and/or
input values as provided filenames are completed internally using
util::complete_path (after which <file> becomes <\\foo\path\file> etc. in this
case).

I tried to disable this assertion (actually, there's two; one in the
constructor and one in the set_file member function) and didn't see any
strange behaviour. E.g. std::ifstream handling with UNC-paths in
iteration_context_policies::load_file_to_string::inner<> worked just fine, as
expected from a native STL.

Goes without saying that I'm using the latest Boost version (1.47.0). I would
be very pleased if anyone could shed some light on this matter or better still
- fix it permanently.

Br,
        Pekka