docs: @Override
      public void setValueAt(Object value, int row, int column) {
          switch (column) {
          case 0:
              String expr = value.toString();
              expressions.set(row, expr);
              String result = "";
              if (expr.length() > 0) {
                  result = debugGui.dim.eval(expr);
                  if (result == null) result = "";
              }
              values.set(row, result);
              updateModel();
              if (row + 1 == expressions.size()) {
                  expressions.add("");
                  values.add("");
                  fireTableRowsInserted(row + 1, row + 1);
              }
              break;
          case 1:
              // just reset column 2; ignore edits
              fireTableDataChanged();
          }
      }