tests whether the provided forms are counted sequences
(counted? form+) (!counted? form+) (is-counted form)
If all forms evaluate to a valid sequence than can report its length without counting, then this function will return #t (true). The first non-counted sequence will result in the function returning #f (false).
(counted? '(1 2 3 4) [5 6 7 8])
This example will return #t (true).
Like most predicates, this function can also be negated by prepending the
! character. This means that all of the provided forms must not be valid counted sequences.
(!counted? "hello" 99)
This example will return #f (false) because strings are counted sequences.