regression/finalize.sml

   1 structure F = MLton.Finalizable
   2
   3 val n = 4
   4 val fs = Array.tabulate (n, fn i =>
   5                          let
   6                             val f = F.new i
   7                             val _ =
   8                                F.addFinalizer
   9                                (f, fn i =>
  10                                 print (concat [Int.toString i, " gone.\n"]))
  11                          in
  12                             f
  13                          end)
  14 fun sub i = F.withValue (Array.sub (fs, i), fn i => i)
  15 val f = F.new 13
  16 fun clear i = Array.update (fs, i, f)
  17 val _ = clear 3
  18 val _ = clear 2
  19 val _ = MLton.GC.collect ()
  20 fun pi x = print (concat [Int.toString x, "\n"])
  21 val _ = pi (sub 0 + sub 1)
  22 val _ = clear 1
  23 val _ = MLton.GC.collect ()
  24 val _ = pi (sub 0)
  25 val _ = clear 0
  26 val _ = MLton.GC.collect ()