for 1 to 9 as \1
  for 1 to 9 as \2
  end for
  break
end for

# (for (@ 1 0-3) ‘1’ ‘9’ (.variable ‘\1’)
#   (.inner
#     (for (@ 2 2-5) ‘1’ ‘9’ (.variable ‘\2’)
#       (.inner nil)
#     )
#     (break (@ 4 2-7))
#   )
# )