if 1
  if 0
  else
    break
  end if
end if

# (if (@ 1 0-2) ‘1’
#   (.inner
#     (if (@ 2 2-4) ‘0’
#       (.inner nil)
#       (.otherwise
#         (break (@ 4 4-9))
#       )
#     )
#   )
#   (.otherwise nil)
# )
# :4:4–9: error: ‘break’ outside ‘for’
#      break
#      ^^^^^