enum

Enum

!i

enum, a.k.a. til, range (from Python), iota (from APL), generates a list of integers between 0 and a given integer x.

 !5
0 1 2 3 4

Dialects based on k6 support negative integers - the generated range in that case is between x and 0:

 !-5
-5 -4 -3 -2 -1

Odometer is an extension of enum for int lists.