Have 2 text in Google Doc table

[Edward Ulle]

Is there any way to have to text values in a cell of a Google Doc table.  I am working on an app where you can sum the values of a Google Doc table.  Like in Word you can have some formulas in a table cell like sum the above rows.  In Google Doc I was thinking of the same thing.  You enter a formula and the value is displayed.  Unfortunately when the value is displayed the formula is lost.  I thought of comment but that isn't easy to implement using script.  Any other ideas?

Right now I have a sidebar where I can choose the formula and the script sums the values.  I can sum rows or columns and do math between 2 rows or columns.  But want to keep the formulas.  I also understand there is no onEdit in Docs so if the table changes the values aren't automatically updated like Sheets but in the sidebar push a button and the table updates.  I'm also thinking display values or formulas.