-- Iteration 19, the storage half: a Float is a real @table column. It is
-- stored, read back bit-exact, indexed (unique, on the TOTAL order — so
-- -0.0 and +0.0 are the same key), and order-by sorts by that total order
-- rather than by raw bits, which would put negatives backwards and drop NaN
-- wherever the comparison sequence happened to leave it.
@table(name: "readings", index: [at])
class Reading {
  at: Float
  label: Text
}

class Priced {
  cost: Float @unique
}

fn main() {
  insert Reading { at: 1.5, label: "b" }
  insert Reading { at: -2.5, label: "a" }
  insert Reading { at: 0.25, label: "c" }

  -- ascending: -2.5 < 0.25 < 1.5. Raw-bit ordering would put -2.5 last.
  for r in from x in Reading order by x.at select x { print("${r.at} ${r.label}") }
  print("--")
  for r in from x in Reading order by x.at desc select x { print("${r.at} ${r.label}") }
  print("--")

  -- edge values survive storage and come back bit-exact
  insert Reading { at: 1.0 / 0.0, label: "inf" }
  insert Reading { at: 0.0 / 0.0, label: "nan" }
  insert Reading { at: -0.0, label: "negzero" }
  for r in from x in Reading order by x.at select x { print("${r.at} ${r.label}") }
  print("--")

  -- a unique Float index keys on the total order: -0.0 and +0.0 are the
  -- SAME key, so the second insert is refused
  print_int(insert Priced { cost: -0.0 })
  let dup = try insert Priced { cost: 0.0 } catch (e) nil
  if dup == nil { print("ZERO-SIGN-DUP-REFUSED") }
  print_int(insert Priced { cost: 0.5 })
}