DecayStringGrammar.h

/**************************************************************************
 * basf2 (Belle II Analysis Software Framework)                           *
 * Author: The Belle II Collaboration                                     *
 *                                                                        *
 * See git log for contributors and copyright holders.                    *
 * This file is licensed under LGPL-3.0, see LICENSE.md.                  *
 **************************************************************************/
 
#pragma once
#define BOOST_SPIRIT_UNICODE
#include <boost/spirit/include/qi.hpp>
#include <analysis/DecayDescriptor/DecayStringParticle.h>
#include <analysis/DecayDescriptor/DecayStringDecay.h>
#include <analysis/DecayDescriptor/DecayString.h>
#include <vector>
#include <string>
 
namespace Belle2 {
  template <typename Iterator>
  struct DecayStringGrammar : boost::spirit::qi::grammar<Iterator, DecayString(), boost::spirit::unicode::space_type> {
    DecayStringGrammar() : DecayStringGrammar::base_type(start)
    {
      using boost::spirit::unicode::char_;
      using boost::spirit::unicode::string;
      using boost::spirit::unicode::space;
      using boost::spirit::qi::lit;
      using boost::spirit::qi::lexeme;
      using boost::spirit::repeat;
 
 
      // Reserved characters for steering - cppcheck doesn't understand the
      // boost::spirit syntax so we suppress warnings. we can't initialise
      // these in the initialisation list because we need things from the
      // namespace
      //
      // cppcheck-suppress incorrectCharBooleanError
      // cppcheck-suppress useInitializationList
      reserved = space || '^' || '[' || ']' || '>' || ':' || '.' || '?' || '!' || '@';
 
      // particle composed of selector, particle name, and user label: "^D_s+:label"
      particle %= *selector >> lexeme[+(char_ - reserved)] >> -label;
      // cppcheck-suppress useInitializationList
      selector = string("^") | string("@") | string("(misID)") | string("(decay)");
      label %= lit(":") >> lexeme[+(char_ - reserved)];
 
      // Arrow types
      arrow %= string("->") | string("=direct=>") | string("=norad=>") | string("=exact=>");
 
      // Keyword for custom MC Matching
      keyword = string("...") | string("?nu") | string("!nu") | string("?gamma") | string("!gamma") | string("?addbrems");
      keywordlist = *keyword;
 
      // Basic decay: mother -> daughterlist
      decay %= particle >> arrow >> daughterlist >> -keywordlist;
      daughterdecay %= lit("[") >> decay >> lit("]");
      daughter %= daughterdecay | particle;
      daughterlist %= +daughter;
 
      // This rule is where the parser starts
      // The decay string can be either a single decay or a list of decays
      start %=  decay | particle;
    }
    boost::spirit::qi::rule<Iterator> reserved;
    boost::spirit::qi::rule<Iterator, DecayStringParticle(), boost::spirit::unicode::space_type> particle;
    boost::spirit::qi::rule<Iterator, std::string(), boost::spirit::unicode::space_type> selector;
    boost::spirit::qi::rule<Iterator, std::string(), boost::spirit::unicode::space_type> label;
    boost::spirit::qi::rule<Iterator, std::string(), boost::spirit::unicode::space_type> arrow;
    boost::spirit::qi::rule<Iterator, std::string(), boost::spirit::unicode::space_type> keyword;
    boost::spirit::qi::rule<Iterator, std::vector<std::string>(), boost::spirit::unicode::space_type> keywordlist;
    boost::spirit::qi::rule<Iterator, DecayStringDecay(), boost::spirit::unicode::space_type> decay;
    boost::spirit::qi::rule<Iterator, DecayStringDecay(), boost::spirit::unicode::space_type> daughterdecay;
    boost::spirit::qi::rule<Iterator, DecayString(), boost::spirit::unicode::space_type> daughter;
    boost::spirit::qi::rule<Iterator, std::vector<DecayString>(), boost::spirit::unicode::space_type> daughterlist;
    boost::spirit::qi::rule<Iterator, DecayString(), boost::spirit::unicode::space_type> start;
  };
}