(windows len src)
  len: an int
  src: an arr
  returns an iter
F

Iterates over overlapping sub-arrays.

Each array produced by the iterator is newly-allocated and mutable, with exactly len elements. If src has fewer than len elements, the iterator yields nothing.

(let it (windows 3 '(0 1 2 3 4)))
(prn ..it) ; prints (0 1 2) (1 2 3) (2 3 4)
rchunks-exact
lines