code: private State skipCommaSpaces(State state) throws IOException {
          wsp1: for (;;) {
              switch (state.current) {
                  default:
                      break wsp1;
                  case 0x20:
                  case 0x9:
                  case 0xD:
                  case 0xA:
              }
              state.current = state.reader.read();
              state = appendToContext(state);
          }
          if (state.current == ',') {
              wsp2: for (;;) {
                  switch (state.current = state.reader.read()) {
                      default:
                          state = appendToContext(state);
                          break wsp2;
                      case 0x20:
                      case 0x9:
                      case 0xA:
                      case 0xD:
                          state = appendToContext(state);
                  }
              }
          }
          return state;
      }
docs: Skips the whitespaces and an optional comma.