C++ Option::getValueExpectedFlag方法代码示例

/// HandlePrefixedOrGroupedOption - The specified argument string (which started
/// with at least one '-') does not fully match an available option.  Check to
/// see if this is a prefix or grouped option.  If so, split arg into output an
/// Arg/Value pair and return the Option to parse it with.
static Option *HandlePrefixedOrGroupedOption(string& Arg, string &Value,
                                             bool &ErrorParsing,
                                         const unordered_map<string, Option*> &OptionsMap) {
  if (Arg.size() == 1) return 0;

  // Do the lookup!
  size_t Length = 0;
  Option *PGOpt = getOptionPred(Arg, Length, isPrefixedOrGrouping, OptionsMap);
  if (PGOpt == 0) return 0;

  // If the option is a prefixed option, then the value is simply the
  // rest of the name...  so fall through to later processing, by
  // setting up the argument name flags and value fields.
  if (PGOpt->getFormattingFlag() == cl::Prefix) {
    Value = Arg.substr(Length);
    Arg = Arg.substr(0, Length);
    assert(OptionsMap.count(Arg) && OptionsMap.find(Arg)->second == PGOpt);
    return PGOpt;
  }

  // This must be a grouped option... handle them now.  Grouping options can't
  // have values.
  assert(isGrouping(PGOpt) && "Broken getOptionPred!");

  do {
    // Move current arg name out of Arg into OneArgName.
    string OneArgName = Arg.substr(0, Length);
    Arg = Arg.substr(Length);

    // Because ValueRequired is an invalid flag for grouped arguments,
    // we don't need to pass argc/argv in.
    assert(PGOpt->getValueExpectedFlag() != cl::ValueRequired &&
           "Option can not be cl::Grouping AND cl::ValueRequired!");
    int Dummy = 0;
    string dummystr;
    ErrorParsing |= ProvideOption(PGOpt, OneArgName,
                                  dummystr, 0, 0, Dummy);

    // Get the next grouping option.
    PGOpt = getOptionPred(Arg, Length, isGrouping, OptionsMap);
  } while (PGOpt && Length != Arg.size());

  // Return the last option with Arg cut down to just the last one.
  return PGOpt;
}

//.........这里部分代码省略.........
      ArgName = argv[i]+1;
      Handler = LookupOption(ArgName, Value, Opts);

      // Check to see if this "option" is really a prefixed or grouped argument.
      if (Handler == 0) {
        std::string RealName(ArgName);
        if (RealName.size() > 1) {
          size_t Length = 0;
          Option *PGOpt = getOptionPred(RealName, Length, isPrefixedOrGrouping,
                                        Opts);

          // If the option is a prefixed option, then the value is simply the
          // rest of the name...  so fall through to later processing, by
          // setting up the argument name flags and value fields.
          //
          if (PGOpt && PGOpt->getFormattingFlag() == cl::Prefix) {
            Value = ArgName+Length;
            assert(Opts.find(std::string(ArgName, Value)) != Opts.end() &&
                   Opts.find(std::string(ArgName, Value))->second == PGOpt);
            Handler = PGOpt;
          } else if (PGOpt) {
            // This must be a grouped option... handle them now.
            assert(isGrouping(PGOpt) && "Broken getOptionPred!");

            do {
              // Move current arg name out of RealName into RealArgName...
              std::string RealArgName(RealName.begin(),
                                      RealName.begin() + Length);
              RealName.erase(RealName.begin(), RealName.begin() + Length);

              // Because ValueRequired is an invalid flag for grouped arguments,
              // we don't need to pass argc/argv in...
              //
              assert(PGOpt->getValueExpectedFlag() != cl::ValueRequired &&
                     "Option can not be cl::Grouping AND cl::ValueRequired!");
              int Dummy;
              ErrorParsing |= ProvideOption(PGOpt, RealArgName.c_str(),
                                            0, 0, 0, Dummy);

              // Get the next grouping option...
              PGOpt = getOptionPred(RealName, Length, isGrouping, Opts);
            } while (PGOpt && Length != RealName.size());

            Handler = PGOpt; // Ate all of the options.
          }
        }
      }
    }

    if (Handler == 0) {
      if (SinkOpts.empty()) {
        cerr << ProgramName << ": Unknown command line argument '"
             << argv[i] << "'.  Try: '" << argv[0] << " --help'\n";
        ErrorParsing = true;
      } else {
        for (std::vector<Option*>::iterator I = SinkOpts.begin(),
               E = SinkOpts.end(); I != E ; ++I)
          (*I)->addOccurrence(i, "", argv[i]);
      }
      continue;
    }

    // Check to see if this option accepts a comma separated list of values.  If
    // it does, we have to split up the value into multiple values...
    if (Value && Handler->getMiscFlags() & CommaSeparated) {
      std::string Val(Value);