type-of
nil?
bool?
int?
flo?
sym?
char?
arr?
str?
tab?
iter?
obj?
class?
fn?
coro?
rfn?
rdata?
int
flo
char
bool
not
num?
deque?
callable?
expander?
iterable?
(rfn? val) val: any type returns a bool
Returns #t if its argument is a Rust function.
#t