Boost C++ Libraries

boost/spirit/home/qi/nonterminal/simple_trace.hpp

/*=============================================================================
    Copyright (c) 2001-2011 Joel de Guzman
    Copyright (c) 2001-2011 Hartmut Kaiser

    Distributed under the Boost Software License, Version 1.0. (See accompanying
    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
==============================================================================*/
#if !defined(BOOST_SPIRIT_SIMPLE_TRACE_DECEMBER_06_2008_1102AM)
#define BOOST_SPIRIT_SIMPLE_TRACE_DECEMBER_06_2008_1102AM

#if defined(_MSC_VER)
#pragma once
#endif

#include <boost/spirit/home/support/unused.hpp>
#include <boost/spirit/home/qi/nonterminal/debug_handler_state.hpp>
#include <boost/fusion/include/out.hpp>
#include <iostream>
#include <boost/mpl/if.hpp>
#include <boost/mpl/and.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/spirit/home/support/attributes.hpp>

//  The stream to use for debug output
#if !defined(BOOST_SPIRIT_DEBUG_OUT)
#define BOOST_SPIRIT_DEBUG_OUT std::cerr
#endif

//  number of tokens to print while debugging
#if !defined(BOOST_SPIRIT_DEBUG_PRINT_SOME)
#define BOOST_SPIRIT_DEBUG_PRINT_SOME 20
#endif

//  number of spaces to indent
#if !defined(BOOST_SPIRIT_DEBUG_INDENT)
#define BOOST_SPIRIT_DEBUG_INDENT 2
#endif

namespace boost { namespace spirit { namespace qi
{
    namespace detail
    {
        template<typename Char>
        inline void token_printer(std::ostream& o, Char c)
        {
            // allow to customize the token printer routine
            spirit::traits::print_token(o, c);
        }
    }

    struct simple_trace
    {
        int& get_indent() const
        {
            static int indent = 0;
            return indent;
        }

        void print_indent(int n) const
        {
            n *= BOOST_SPIRIT_DEBUG_INDENT;
            for (int i = 0; i != n; ++i)
                BOOST_SPIRIT_DEBUG_OUT << ' ';
        }

        template <typename Iterator>
        void print_some(
            char const* tag
          , int /*indent*/
          , Iterator first, Iterator const& last) const
        {
            print_indent(get_indent());
            BOOST_SPIRIT_DEBUG_OUT << '<' << tag << '>';
            int const n = BOOST_SPIRIT_DEBUG_PRINT_SOME;
            for (int i = 0; first != last && i != n && *first; ++i, ++first)
                detail::token_printer(BOOST_SPIRIT_DEBUG_OUT, *first);
            BOOST_SPIRIT_DEBUG_OUT << "</" << tag << '>' << std::endl;

            // $$$ FIXME convert invalid xml characters (e.g. '<') to valid
            // character entities. $$$
        }

        template <typename Iterator, typename Context, typename State>
        void operator()(
            Iterator const& first
          , Iterator const& last
          , Context const& context
          , State state
          , std::string const& rule_name) const
        {
            switch (state)
            {
                case pre_parse:
                    print_indent(get_indent()++);
                    BOOST_SPIRIT_DEBUG_OUT
                        << '<' << rule_name << '>'
                        << std::endl;
                    print_some("try", get_indent(), first, last);
                    break;
                case successful_parse:
                    print_some("success", get_indent(), first, last);
                    print_indent(get_indent());
                    BOOST_SPIRIT_DEBUG_OUT
                        << "<attributes>";
                    traits::print_attribute(
                        BOOST_SPIRIT_DEBUG_OUT,
                        context.attributes
                    );
                    BOOST_SPIRIT_DEBUG_OUT
                        << "</attributes>";
                    if (!fusion::empty(context.locals))
                        BOOST_SPIRIT_DEBUG_OUT
                            << "<locals>"
                            << context.locals
                            << "</locals>";
                    BOOST_SPIRIT_DEBUG_OUT << std::endl;
                    print_indent(--get_indent());
                    BOOST_SPIRIT_DEBUG_OUT
                        << "</" << rule_name << '>'
                        << std::endl;
                    break;
                case failed_parse:
                    print_indent(get_indent());
                    BOOST_SPIRIT_DEBUG_OUT << "<fail/>" << std::endl;
                    print_indent(--get_indent());
                    BOOST_SPIRIT_DEBUG_OUT
                        << "</" << rule_name << '>'
                        << std::endl;
                    break;
            }
        }
    };
}}}

#endif