anchor.diff:                                                                  'density_matrices', 'density_matrix_file', 'even_selection', &
                                                                   'multiref', 'n_secondary_ref']
           character(10) :: string
  +        character(28), dimension(:), allocatable :: keys_concat
   
           if (aot_exists(lua_state, opts, 'ccmc')) then
   
  
positive.code:                 if (ccmc_in%n_secondary_ref == 0) then
                      call stop_all('read_ccmc_in', 'Number of secondary references unspecified.') 
                  end if
                  allocate(ccmc_in%secondary_refs(ccmc_in%n_secondary_ref))
                  do i = 1, ccmc_in%n_secondary_ref
                      if (i<10) then
  
negative.code:         !        full space if present.
          !    ref_table_name (optional): name of table holding reference info.  Default: reference.
          ! Out:
          !    ref: reference_t object containing the input options describing the
          !        reference.  Note that ex_level is set to the number of electrons
          !        if not provided (incl. if the reference table is not present in
          !        opts) and sys is present and -1 otherwise.
  