Since version 1.2.0, it has been possible to reference created formulas using curly brackets.

Since version 3.1.0, formulas can also be named and referenced with a name.

So if you want to use the result of formula 1 in your new formula, you can simply enter the following:

{1} or {allMyDucks}

More generally:

{NumberOfFormula} or {NameOfFormula}