It would be so sweet if the "(" and ")" were defined as push/pop from a secondary stack. So "(+ 1 2)" would always be equal to "1 2 +". : ABS (IF (< DUP 0)) (

It would be so sweet if the "(" and ")" were defined as push/pop from a secondary stack. So "(+ 1 2)" would always be equal to "1 2 +". : ABS (IF (< DUP 0)) (THEN (- 0 SWAP)) ;