CC.cpp

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#include <Gaudi/Decays/CC.h>
 
namespace Decays = Gaudi::Decays;
 
namespace {
  inline std::string cc_( const std::string& decay, const Decays::CC::MapCC& map_,
                          const std::string::size_type pos = 0 ) {
    // check the validity of position
    if ( pos >= decay.size() ) { return decay; }
    // find the match:
    auto                              _p = std::string::npos;
    Decays::CC::MapCC::const_iterator _i = map_.end();
    // look for the "nearest" and "longest" match
    for ( auto ic = map_.begin(); map_.end() != ic; ++ic ) {
      // find the particle
      std::string::size_type p = decay.find( ic->first, pos );
      // match?
      if ( std::string::npos == p ) { continue; }
      // find the nearest match
      if ( p < _p ) {
        _p = p;
        _i = ic;
      }
    }
    // no match at all.
    if ( std::string::npos == _p || map_.end() == _i ) { return decay; }
 
    // replace
    std::string aux = decay;
    aux.replace( _p, _i->first.size(), _i->second );
 
    // advance the position
    _p += _i->second.size();
    // ... and start the recursion here
    return _p < aux.size() ? cc_( aux, map_, _p ) : aux;
  }
} // namespace
/* simple function to make charge conjugated inside the original string.
 *  All substrings are substituted by their charge conjugates
 *  @param decay the original string
 *  @param map_  the full map of substitutions
 *  @return charge-conjugated string
 */
 
std::string Decays::CC::cc( const std::string& decay, const Decays::CC::MapCC& map_ ) { return cc_( decay, map_ ); }
 
std::string Decays::CC::cc( const std::string& decay, const std::map<std::string, std::string>& map_ ) {
  return cc_( decay, { map_.begin(), map_.end() } );
}