fact: Fixpoint nztail d := match d with | Nil => Nil | D0 d => match nztail d with Nil => Nil | d' => D0 d' end | D1 d => D1 (nztail d) | D2 d => D2 (nztail d) | D3 d => D3 (nztail d) | D4 d => D4 (nztail d) | D5 d => D5 (nztail d) | D6 d => D6 (nztail d) | D7 d => D7 (nztail d) | D8 d => D8 (nztail d) | D9 d => D9 (nztail d) end.
imports: Decimal Arith ZArith