If it is combined with setting uninitialized variables to zero type 1 it is reasonable.
/ Martin Nilsson (Åskblod)
Previous text:
2003-01-23 01:22: Subject: Re: zero_type() & UNDEFINED and _typeof()
Well, it isn't that unreasonable to add a new function undefined() that is implemented as (zero_type(x) == 1). It's common that people don't check the exact zero type. That's almost never a problem but it can easily become too much of a habit, which occasionally has led to bugs.
/ Martin Stjernholm, Roxen IS