docs: function parse_BrtArrFmla(data, length, opts) {
  	var end = data.l + length;
  	var rfx = parse_RfX(data, 16);
  	var fAlwaysCalc = data.read_shift(1);
  	var o = [rfx]; o[2] = fAlwaysCalc;
  	if(opts.cellFormula) {
  		var formula = parse_XLSBArrayParsedFormula(data, end - data.l, opts);
  		o[1] = formula;
  	} else data.l = end;
  	return o;
  }