/*============================================================================= | |
Copyright (c) 2001-2011 Joel de Guzman | |
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_INFO_NOVEMBER_22_2008_1132AM) | |
#define BOOST_SPIRIT_INFO_NOVEMBER_22_2008_1132AM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/variant/variant.hpp> | |
#include <boost/variant/recursive_variant.hpp> | |
#include <boost/variant/apply_visitor.hpp> | |
#include <boost/foreach.hpp> | |
#include <boost/spirit/home/support/utf8.hpp> | |
#include <list> | |
#include <iterator> | |
#include <utility> | |
namespace boost { namespace spirit | |
{ | |
// info provides information about a component. Each component | |
// has a what member function that returns an info object. | |
// strings in the info object are assumed to be encoded as UTF8 | |
// for uniformity. | |
struct info | |
{ | |
struct nil {}; | |
typedef | |
boost::variant< | |
nil | |
, utf8_string | |
, recursive_wrapper<info> | |
, recursive_wrapper<std::pair<info, info> > | |
, std::list<info> | |
> | |
value_type; | |
explicit info(utf8_string const& tag) | |
: tag(tag), value(nil()) {} | |
template <typename T> | |
info(utf8_string const& tag, T const& value) | |
: tag(tag), value(value) {} | |
info(utf8_string const& tag, char value) | |
: tag(tag), value(utf8_string(1, value)) {} | |
info(utf8_string const& tag, wchar_t value) | |
: tag(tag), value(to_utf8(value)) {} | |
info(utf8_string const& tag, ucs4_char value) | |
: tag(tag), value(to_utf8(value)) {} | |
template <typename Char> | |
info(utf8_string const& tag, Char const* str) | |
: tag(tag), value(to_utf8(str)) {} | |
template <typename Char, typename Traits, typename Allocator> | |
info(utf8_string const& tag | |
, std::basic_string<Char, Traits, Allocator> const& str) | |
: tag(tag), value(to_utf8(str)) {} | |
utf8_string tag; | |
value_type value; | |
}; | |
template <typename Callback> | |
struct basic_info_walker | |
{ | |
typedef void result_type; | |
typedef basic_info_walker<Callback> this_type; | |
basic_info_walker(Callback& callback, utf8_string const& tag, int depth) | |
: callback(callback), tag(tag), depth(depth) {} | |
void operator()(info::nil) const | |
{ | |
callback.element(tag, "", depth); | |
} | |
void operator()(utf8_string const& str) const | |
{ | |
callback.element(tag, str, depth); | |
} | |
void operator()(info const& what) const | |
{ | |
boost::apply_visitor( | |
this_type(callback, what.tag, depth+1), what.value); | |
} | |
void operator()(std::pair<info, info> const& pair) const | |
{ | |
callback.element(tag, "", depth); | |
boost::apply_visitor( | |
this_type(callback, pair.first.tag, depth+1), pair.first.value); | |
boost::apply_visitor( | |
this_type(callback, pair.second.tag, depth+1), pair.second.value); | |
} | |
void operator()(std::list<info> const& l) const | |
{ | |
callback.element(tag, "", depth); | |
BOOST_FOREACH(info const& what, l) | |
{ | |
boost::apply_visitor( | |
this_type(callback, what.tag, depth+1), what.value); | |
} | |
} | |
Callback& callback; | |
utf8_string const& tag; | |
int depth; | |
private: | |
// silence MSVC warning C4512: assignment operator could not be generated | |
basic_info_walker& operator= (basic_info_walker const&); | |
}; | |
// bare-bones print support | |
template <typename Out> | |
struct simple_printer | |
{ | |
typedef utf8_string string; | |
simple_printer(Out& out) | |
: out(out) {} | |
void element(string const& tag, string const& value, int /*depth*/) const | |
{ | |
if (value == "") | |
out << '<' << tag << '>'; | |
else | |
out << '"' << value << '"'; | |
} | |
Out& out; | |
private: | |
// silence MSVC warning C4512: assignment operator could not be generated | |
simple_printer& operator= (simple_printer const&); | |
}; | |
template <typename Out> | |
Out& operator<<(Out& out, info const& what) | |
{ | |
simple_printer<Out> pr(out); | |
basic_info_walker<simple_printer<Out> > walker(pr, what.tag, 0); | |
boost::apply_visitor(walker, what.value); | |
return out; | |
} | |
}} | |
#endif |