procedure show(t)
   local x

   write("   *t --> ", *t)
   write("   t[\"xyz\"] --> ", image(t["xyz"]) | "failure")
   write("   member(t, \"xyz\") --> ", image(member(t, "xyz")) | "failure")
   x := sort(t, 3)
   write("   contents of t:")
   while writes("\t", image(get(x)), " : ")
      do write(image(get(x)))
   write("")
end

procedure main()
   local t

   write("t := table(\"default\") --> ", image(t := table("default")) |
      "failure")
   show(t)
   write("insert(t, 3, 4) --> ", image(insert(t, 3, 4)) | "failure")
   write("insert(t, \"xyz\", \"abc\") --> ", image(insert(t, "xyz", "abc")) |
      "failure")
   write("insert(t, &digits) --> ", image(insert(t, &digits)) | "failure")
   show(t)
   write("t[\"xyz\"] := \"new value\" --> ", image(t["xyz"] := "new value") |
      "failure")
   show(t)
   write("insert(t, \"xyz\", \"def\") --> ", image(insert(t, "xyz", "def")) |
      "failure")
   show(t)
   write("delete(t, \"xyz\") -- > ", image(delete(t, "xyz")) | "failure")
   show(t)
   write("delete(t, \"xyz\") -- > ", image(delete(t, "xyz")) | "failure")
   show(t)
end