spirit/example/support/utree/error_handler.hpp
2018-11-11 23:14:05 +00:00

113 lines
2.6 KiB
C++

/*==============================================================================
Copyright (c) 2001-2011 Joel de Guzman
Copyright (c) 2010-2011 Bryce Lelbach
Distributed under the Boost Software License, Version 1.0. (See accompanying
file BOOST_LICENSE_1_0.rst or copy at http://www.boost.org/LICENSE_1_0.txt)
==============================================================================*/
#if !defined(BOOST_SPIRIT_UTREE_EXAMPLE_ERROR_HANDLER_HPP)
#define BOOST_SPIRIT_UTREE_EXAMPLE_ERROR_HANDLER_HPP
#include <string>
#include <sstream>
#include <boost/config.hpp>
#include <boost/spirit/home/support/info.hpp>
#include <boost/spirit/include/support_line_pos_iterator.hpp>
namespace sexpr
{
using boost::spirit::info;
template <typename Out>
struct print_info
{
typedef boost::spirit::utf8_string string;
print_info(Out& out) : out(out), first(true) {}
void element(string const& tag, string const& value, int) const
{
if (!first) {
out << ' ';
first = false;
}
if (value == "")
out << tag;
else
out << "\"" << value << '"';
}
Out& out;
mutable bool first;
};
struct expected_component : std::exception
{
std::string msg;
expected_component(std::string const& source, std::size_t line
, info const& w)
{
using boost::spirit::basic_info_walker;
std::ostringstream oss;
oss << "(exception \"" << source << "\" ";
if (line == -1)
oss << -1;
else
oss << line;
oss << " '(expected_component (";
print_info<std::ostringstream> pr(oss);
basic_info_walker<print_info<std::ostringstream> >
walker(pr, w.tag, 0);
boost::apply_visitor(walker, w.value);
oss << ")))";
msg = oss.str();
}
virtual ~expected_component() BOOST_NOEXCEPT_OR_NOTHROW {}
virtual char const* what() const BOOST_NOEXCEPT_OR_NOTHROW
{
return msg.c_str();
}
};
template <typename Iterator>
struct error_handler
{
template <typename, typename, typename, typename>
struct result
{
typedef void type;
};
std::string source;
error_handler(std::string const& source_ = "<string>") : source(source_) {}
void operator()(Iterator first, Iterator last, Iterator err_pos
, info const& what) const
{
using boost::spirit::get_line;
Iterator eol = err_pos;
std::size_t line = get_line(err_pos);
throw expected_component(source, line, what);
}
};
} // sexpr
#endif // BOOST_SPIRIT_UTREE_EXAMPLE_ERROR_HANDLER_HPP