@ being inserted in formulas using structure references

[beniutek]

so I have a function, that simple inserts a formula into a cell in the sheet.

    def write_formula_row(sheet, start_row, start_column, type)
      formula = "=SUM(SUBTOTAL(3,OFFSET(Database!$E$1,IF(table1[#{type}]=\"#{type}\",ROW(db_table[Break])-1,0),0)))"

      sheet.write_formula(start_row, start_column, formula, body1)
    end

In other worksheet I have a table and type string is the same as the column name of that table
Now, when I create an excel file and go to my worksheet I see that there are errors in this formula and upon investigation i see that instead of (let's say type is "Foo") formula being like below:

=SUM(SUBTOTAL(3,OFFSET(Database!$E$1,IF(table1[Foo]=\"Foo",ROW(db_table[Break])-1,0),0)))

the formula in excel looks like below:

=SUM(SUBTOTAL(3,OFFSET(Database!$E$1,IF(table1[@Foo]=\"Foo",ROW(db_table[Break])-1,0),0)))

so @ has been added. After I remove @ manually the formula works perfectly.

I don't know how to tell the library to not add this additional @ in the structured reference.

Is this an issue with the library or with my code?