So do all the implicit assumptions in duck-typed code, but following them relies fully on the programmer's own caution. You can of course add explicit checks a

So do all the implicit assumptions in duck-typed code, but following them relies fully on the programmer's own caution. You can of course add explicit checks and tests, eventually paying the same amount (or more) in LOC as the typed implementation's initial cost, but then you're also tasked to keep those up to date, without the compiler's aid.