boost/date_time/date_generator_parser.hpp
#ifndef DATE_TIME_DATE_GENERATOR_PARSER_HPP__ #define DATE_TIME_DATE_GENERATOR_PARSER_HPP__ /* Copyright (c) 2005 CrystalClear Software, Inc. * Use, modification and distribution is subject to the * Boost Software License, Version 1.0. (See accompanying * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) * Author: Jeff Garland, Bart Garst * $Date$ */ #include <string> #include <vector> #include <iterator> // istreambuf_iterator #include <boost/throw_exception.hpp> #include <boost/date_time/compiler_config.hpp> #include <boost/date_time/string_parse_tree.hpp> #include <boost/date_time/date_generators.hpp> #include <boost/date_time/format_date_parser.hpp> namespace boost { namespace date_time { //! Class for date_generator parsing /*! The elements of a date_generator "phrase" are parsed from the input stream in a * particular order. All elements are required and the order in which they appear * cannot change, however, the elements themselves can be changed. The default * elements and their order are as follows: * * - partial_date => "dd Month" * - nth_day_of_the_week_in_month => "nth weekday of month" * - first_day_of_the_week_in_month => "first weekday of month" * - last_day_of_the_week_in_month => "last weekday of month" * - first_day_of_the_week_after => "weekday after" * - first_day_of_the_week_before => "weekday before" * * Weekday and Month names and formats are handled via the date_input_facet. * */ template<class date_type, typename charT> class date_generator_parser { public: typedef std::basic_string<charT> string_type; typedef std::istreambuf_iterator<charT> stream_itr_type; typedef typename date_type::month_type month_type; typedef typename date_type::day_of_week_type day_of_week_type; typedef typename date_type::day_type day_type; typedef string_parse_tree<charT> parse_tree_type; typedef typename parse_tree_type::parse_match_result_type match_results; typedef std::vector<std::basic_string<charT> > collection_type; typedef partial_date<date_type> partial_date_type; typedef nth_kday_of_month<date_type> nth_kday_type; typedef first_kday_of_month<date_type> first_kday_type; typedef last_kday_of_month<date_type> last_kday_type; typedef first_kday_after<date_type> kday_after_type; typedef first_kday_before<date_type> kday_before_type; typedef charT char_type; static const char_type first_string[6]; static const char_type second_string[7]; static const char_type third_string[6]; static const char_type fourth_string[7]; static const char_type fifth_string[6]; static const char_type last_string[5]; static const char_type before_string[8]; static const char_type after_string[6]; static const char_type of_string[3]; enum phrase_elements {first=0, second, third, fourth, fifth, last, before, after, of, number_of_phrase_elements}; //! Creates a date_generator_parser with the default set of "element_strings" date_generator_parser() { element_strings(string_type(first_string), string_type(second_string), string_type(third_string), string_type(fourth_string), string_type(fifth_string), string_type(last_string), string_type(before_string), string_type(after_string), string_type(of_string)); } //! Creates a date_generator_parser using a user defined set of element strings date_generator_parser(const string_type& first_str, const string_type& second_str, const string_type& third_str, const string_type& fourth_str, const string_type& fifth_str, const string_type& last_str, const string_type& before_str, const string_type& after_str, const string_type& of_str) { element_strings(first_str, second_str, third_str, fourth_str, fifth_str, last_str, before_str, after_str, of_str); } //! Replace strings that determine nth week for generator void element_strings(const string_type& first_str, const string_type& second_str, const string_type& third_str, const string_type& fourth_str, const string_type& fifth_str, const string_type& last_str, const string_type& before_str, const string_type& after_str, const string_type& of_str) { collection_type phrases; phrases.push_back(first_str); phrases.push_back(second_str); phrases.push_back(third_str); phrases.push_back(fourth_str); phrases.push_back(fifth_str); phrases.push_back(last_str); phrases.push_back(before_str); phrases.push_back(after_str); phrases.push_back(of_str); m_element_strings = parse_tree_type(phrases, this->first); // enum first } void element_strings(const collection_type& col) { m_element_strings = parse_tree_type(col, this->first); // enum first } //! returns partial_date parsed from stream template<class facet_type> partial_date_type get_partial_date_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } day_type d(1); month_type m(1); facet.get(sitr, stream_end, a_ios, d); facet.get(sitr, stream_end, a_ios, m); return partial_date_type(d,m); } //! returns nth_kday_of_week parsed from stream template<class facet_type> nth_kday_type get_nth_kday_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } typename nth_kday_type::week_num wn; day_of_week_type wd(0); // no default constructor month_type m(1); // no default constructor match_results mr = m_element_strings.match(sitr, stream_end); switch(mr.current_match) { case first : { wn = nth_kday_type::first; break; } case second : { wn = nth_kday_type::second; break; } case third : { wn = nth_kday_type::third; break; } case fourth : { wn = nth_kday_type::fourth; break; } case fifth : { wn = nth_kday_type::fifth; break; } default: { boost::throw_exception(std::ios_base::failure("Parse failed. No match found for '" + mr.cache + "'")); BOOST_DATE_TIME_UNREACHABLE_EXPRESSION(wn = nth_kday_type::first); } } // week num facet.get(sitr, stream_end, a_ios, wd); // day_of_week extract_element(sitr, stream_end, of); // "of" element facet.get(sitr, stream_end, a_ios, m); // month return nth_kday_type(wn, wd, m); } //! returns first_kday_of_week parsed from stream template<class facet_type> first_kday_type get_first_kday_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } day_of_week_type wd(0); // no default constructor month_type m(1); // no default constructor extract_element(sitr, stream_end, first); // "first" element facet.get(sitr, stream_end, a_ios, wd); // day_of_week extract_element(sitr, stream_end, of); // "of" element facet.get(sitr, stream_end, a_ios, m); // month return first_kday_type(wd, m); } //! returns last_kday_of_week parsed from stream template<class facet_type> last_kday_type get_last_kday_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } day_of_week_type wd(0); // no default constructor month_type m(1); // no default constructor extract_element(sitr, stream_end, last); // "last" element facet.get(sitr, stream_end, a_ios, wd); // day_of_week extract_element(sitr, stream_end, of); // "of" element facet.get(sitr, stream_end, a_ios, m); // month return last_kday_type(wd, m); } //! returns first_kday_of_week parsed from stream template<class facet_type> kday_before_type get_kday_before_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } day_of_week_type wd(0); // no default constructor facet.get(sitr, stream_end, a_ios, wd); // day_of_week extract_element(sitr, stream_end, before);// "before" element return kday_before_type(wd); } //! returns first_kday_of_week parsed from stream template<class facet_type> kday_after_type get_kday_after_type(stream_itr_type& sitr, stream_itr_type& stream_end, std::ios_base& a_ios, const facet_type& facet) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } day_of_week_type wd(0); // no default constructor facet.get(sitr, stream_end, a_ios, wd); // day_of_week extract_element(sitr, stream_end, after); // "after" element return kday_after_type(wd); } private: parse_tree_type m_element_strings; //! Extracts phrase element from input. Throws ios_base::failure on error. void extract_element(stream_itr_type& sitr, stream_itr_type& stream_end, typename date_generator_parser::phrase_elements ele) const { // skip leading whitespace while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } match_results mr = m_element_strings.match(sitr, stream_end); if(mr.current_match != ele) { boost::throw_exception(std::ios_base::failure("Parse failed. No match found for '" + mr.cache + "'")); } } }; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::first_string[6] = {'f','i','r','s','t'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::second_string[7] = {'s','e','c','o','n','d'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::third_string[6] = {'t','h','i','r','d'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::fourth_string[7] = {'f','o','u','r','t','h'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::fifth_string[6] = {'f','i','f','t','h'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::last_string[5] = {'l','a','s','t'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::before_string[8] = {'b','e','f','o','r','e'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::after_string[6] = {'a','f','t','e','r'}; template<class date_type, class CharT> const typename date_generator_parser<date_type, CharT>::char_type date_generator_parser<date_type, CharT>::of_string[3] = {'o','f'}; } } //namespace #endif // DATE_TIME_DATE_GENERATOR_PARSER_HPP__