-- update any in-progress animations
-- return whether any work remains
draw_next_frames_of_animations = function()
	local a = Animations_in_progress
	for i=#a,1,-1 do
		if coroutine.status(a[i].co) == 'dead' then
			table.remove(a, i)
		else
			local status, err = coroutine.resume(a[i].co)
			if status == false then error(err) end
		end
	end
	return #a > 0
end

-- Intermediate state during animations.
Animations_in_progress = {}

-- A debugging aid to help animate intermediate results within f.
-- Pause animation in the current frame using loiter().
-- Try to only have one such call in your program.
-- You can have multiple, but things might get confusing if one of them indirectly calls the other,
-- or more generally if a single function ever loiters sometimes under the call tree of one and sometimes under the other.
enable_loiter = function(f, ...)
	local args = {...}
	Error_with_callstack = nil
	local co = coroutine.create(
						function()
							xpcall(function()
											f(unpack(args))
										end,
										save_callstack)
						end)
	coroutine.resume(co, ...)
	if Error_with_callstack then
		error(Error_with_callstack)
	end
	table.insert(Debug_animations_in_progress, {co=co, next_run=Current_time+0.3})
end

  },
  "Animations_in_progress": {
      "x": 5900,
      "y": 31.415451388884,

  },
  "enable_loiter": {
      "x": 7600,
      "y": 284.41545138888,

  },
  "draw_next_frames_of_animations": {
      "x": 6600,
      "y": 297.41545138888,

	draw_next_frames_of_animations()

-- Can only be called from functions invoked using `enable_loiter()`.

-- Can only be called from functions invoked using `animate()`.

	table.insert(Animations_in_progress, {co=co})

	table.insert(Debug_animations_in_progress, {co=co})