anchor.diff:  
       subroutine logging_t_json(js, logging_info, terminal)
   
  +        ! Serialise a logging_t object in JSON format.
  +
  +        ! In/Out:
  +        !   js: json_out_t controlling the output unit and handling JSON internal state.  Unchanged on output.
  +        ! In:
  +        !   logging_info: logging_t object containing logging values used in calculation (including any
  +        !               defaults set).
  +        !   terminal (optional): if true, this is the last entry in the enclosing JSON object.  Default: false.
  +
           use json_out
   
           type(json_out_t), intent(inout) :: js
  
positive.code:         call write_logging_death_preamble(logging_info)
  
      end subroutine init_logging_death
  
      subroutine write_logging_calc_header(logging_info)
          ! Write header and preamble for calculation log file.
  
negative.code: 
      end subroutine end_logging
  
  ! --- Log-specific initialisation functions ---
  
      subroutine init_logging_calc(logging_in, logging_info)
  
  