text: const reducer = (state, action) => {
      switch (action.type) {
          case 'change_directory':
              return {
                  ...state,
                  directory: {
                      ...state.directory,
                      ...action.directory
                  }
              };
          case 'change_note':
              return {
                  ...state,
                  note: { ...action.note }
              };
          default:
              return state;
      }
  };
  export default reducer;
  