split
Given a list and index into that list, return a cons where the car is all elements up to that index (exclusive) and the cdr is the rest of the list.
Basically a wrapper over subseq but for when using `->>` as the list is the last parameter.
Splitting macros and functions into different packages and source code makes it easier to look at. Functions currently implemented: - range: like Python's range - parse-integer*: parse-integer but junk-allowed is set to t.