translateVisualIndexToColumns = function translateVisualIndexToColumns(visualColumnIndex) {
        var arr = [];
        var columnsLen = instance.countSourceCols();
        var index = 0;

        for (; index < columnsLen; index++) {
          if ((0, _function.isFunction)(instance.getSettings().columns) && instance.getSettings().columns(index)) {
            arr.push(index);
          }
        }

        return arr[visualColumnIndex];
      }
Returns an array of column headers (in string format, if they are enabled). If param `column` is given, it
returns the header at the given column.

@memberof Core#
@function getColHeader
@param {Number} [column] Visual column index.
@fires Hooks#modifyColHeader
@returns {Array|String|Number} The column header(s).