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// ----------------------------------------------------------------------------
// Copyright (C) 2002-2006 Marcin Kalicinski
//
// 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)
//
// For more information, see www.boost.org
// ----------------------------------------------------------------------------
#include <boost/property_tree/ptree.hpp>
#include <boost/property_tree/info_parser.hpp>
#include <iostream>
#include <iomanip>
#include <string>
using namespace boost::property_tree;
static ptree dflt;
// Process settings using empty ptree trick. Note that it is considerably simpler
// than version which does not use the "trick"
void process_settings(const std::string &filename)
{
ptree pt;
read_info(filename, pt);
const ptree &settings = pt.get_child("settings", dflt);
std::cout << "\n Processing " << filename << std::endl;
std::cout << " Setting 1 is " << settings.get("setting1", 0) << std::endl;
std::cout << " Setting 2 is " << settings.get("setting2", 0.0) << std::endl;
std::cout << " Setting 3 is " << settings.get("setting3", "default") << std::endl;
}
// Process settings not using empty ptree trick. This one must duplicate much of the code.
void process_settings_without_trick(const std::string &filename)
{
ptree pt;
read_info(filename, pt);
if (boost::optional<ptree &> settings = pt.get_child_optional("settings"))
{
std::cout << "\n Processing " << filename << std::endl;
std::cout << " Setting 1 is " << settings.get().get("setting1", 0) << std::endl;
std::cout << " Setting 2 is " << settings.get().get("setting2", 0.0) << std::endl;
std::cout << " Setting 3 is " << settings.get().get("setting3", "default") << std::endl;
}
else
{
std::cout << "\n Processing " << filename << std::endl;
std::cout << " Setting 1 is " << 0 << std::endl;
std::cout << " Setting 2 is " << 0.0 << std::endl;
std::cout << " Setting 3 is " << "default" << std::endl;
}
}
int main()
{
try
{
std::cout << "Processing settings with empty-ptree-trick:\n";
process_settings("settings_fully-existent.info");
process_settings("settings_partially-existent.info");
process_settings("settings_non-existent.info");
std::cout << "\nProcessing settings without empty-ptree-trick:\n";
process_settings_without_trick("settings_fully-existent.info");
process_settings_without_trick("settings_partially-existent.info");
process_settings_without_trick("settings_non-existent.info");
}
catch (std::exception &e)
{
std::cout << "Error: " << e.what() << "\n";
}
return 0;
}
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