define test_call_fn_stack_failure
  {
  a = 1
  b = 2
  x[1] = 0

  if ("return_noval" in $test_call_fn_stack_failure)
    {
    delete $test_call_fn_stack_failure["return_noval"]
    return
    }
  if ("no_arg" in $test_call_fn_stack_failure)
    {
    delete $test_call_fn_stack_failure["no_arg"]
    c = $1
    }
  if ("undefined" in $test_call_fn_stack_failure)
    {
    delete $test_call_fn_stack_failure["undefined"]
    c = undefined_var
    }
  if ("array_scalar" in $test_call_fn_stack_failure)
    {
    delete $test_call_fn_stack_failure["array_scalar"]
    c = x + a
    }
  c = $test_call_fn_stack_failure["no_such_index"]

  return 0
  }

define test_call_fn_stack_failure_1
  {
  a[1] = 2
  a[2] = 1
  return test_call_fn_stack_failure()
  }

define test_call_fn_stack_failure_reset
  {
  $test_call_fn_stack_failure["return_noval"] = 0
  $test_call_fn_stack_failure["no_arg"] = 0
  $test_call_fn_stack_failure["array_scalar"] = 0
  $test_call_fn_stack_failure["undefined"] = 0
  $test_call_fn_stack_failure["reset"] = 0
  }

define test_call_fn_stack_failure_0
  {
  while (1)
    {
    r = dialog("Perform failure?", "Yes", "No", "Reset")
    if (r == 1)
      test_call_fn_stack_failure_1()
    else if (r == 2)
      break
    else if (r == 3)
      test_call_fn_stack_failure_reset()
    }
  }

$test_call_fn_stack_failure[""] = 0
if (!("reset" in $test_call_fn_stack_failure))
  test_call_fn_stack_failure_reset()
test_call_fn_stack_failure_0()