anchor.diff:          !        Used as the reference determinant if a truncated CI space is
           !        being used.  *MUST* be specified if ex_level is not the number
           !        of electrons in the system.
  +        !    verbose_in(optional): print out info about number of determinants in each symmetry
  +        !        block.  Default: same value as init.
           ! In/Out:
           !    sym_space_size: number of determinants of each symmetry.  Output if init
           !        is true, input if init is false.
  
positive.code: 
  !--- Hilbert space enumeration ---
  
      subroutine enumerate_determinants(sys, init, spin_flip, ex_level, sym_space_size, ndets, dets_list, ref_sym, occ_list0)
  
          ! Find the Slater determinants of a given system that can be formed from
          ! the basis functions.
  
negative.code:         integer, intent(inout), allocatable :: sym_space_size(:) ! (nsym)
          integer, intent(out) :: ndets
          integer(i0), intent(out), allocatable :: dets_list(:,:) ! (string_len,ndets)
          logical, intent(in), optional :: verbose_in
  
          integer :: i, j, iel, idet, ierr
          integer :: nbeta_combinations
  