anchor.diff:          character(4) :: fmt1
           integer(i0) :: f(sys%basis%string_len)
           integer, allocatable :: occ(:), comb(:,:), unocc(:)
  -        integer :: k(sys%lattice%ndim), k_beta(sys%lattice%ndim)
  +        integer :: k(sys%lattice%ndim), k_beta(sys%lattice%ndim), det_unit
           type(det_info_t) :: d0
           logical :: in_space, force_full
   
  
positive.code: ! If true then the determinant list is written to determinant_file.
  logical :: write_determinants = .false.
  character(255) :: determinant_file = 'DETS'
  integer :: det_unit
  
  contains
  
  
negative.code: 
          use utils, only: get_free_unit
  
          integer :: det_unit
  
          if (write_determinants) then
              ! Overwrite any existing file...
              det_unit = get_free_unit()
              open(det_unit, file=determinant_file, status='unknown')
              close(det_unit, status='delete')
          end if
  
      end subroutine init_determinant_enumeration
  
  !--- Hilbert space enumeration ---
  
  