| // ---------------------------------------------------------------------------- |
| // 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; |
| |
| // 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", empty_ptree<ptree>()); |
| 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; |
| } |