`dotted-ilist?``x`procedureTrue if

`x`is a finite, non-nil-terminated ilist. That is, there exists an n >= 0 such that`(icdrn x)`is neither an ipair nor (). This includes non-ipair, non-() values (e.g. symbols, numbers), which are considered to be dotted ilists of length 0.(dotted-ilist? x) = (not (proper-ilist? x))