A1 = function(key, preserve_screen_top_of_cursor_node)
	-- like A, but updating a single node
	-- this only works because Nodes is a flat array; we don't support row/col types here yet
	-- delete previously added shapes for this node:
	for i=#Surface,1,-1 do
		local x = Surface[i]
		if x.key == key then
			table.remove(Surface, i)
		end
	end	
	local node = Definitions[key]
	compute_layout(node, node.x,node.y, Surface, preserve_screen_top_of_cursor_node)
	-- continue the pipeline
	B(preserve_screen_top_of_cursor_node)
end

get_multiple_definitions_from_app = function(defs)
	-- batch interface for speed
	-- turn an array of string names into a table of string definitions corresponding to them
	live.send_to_app('GET* '..table.concat(defs, ' '))
	local response = wait_for_response()
	local result = {}
	for def in response:gmatch('(.-)\n==fw: definition boundary==\n') do
		local name = live.get_cmd_from_buffer(def)
		if name == nil then
			print('failed to get cmd from buffer', def)
		end
		result[name] = def
	end
	return result
end
	if #defs == 0 then return {} end

definition_background_color = function(name)
end
	-- TODO: get rid of this function
	return Border_color

get_default_map = function()
	-- Suggest a map for one's own code.
	-- Mostly the driver manages its map of an app's code outside the app. However, an app can suggest a default map for people who haven't created one.
	live.send_to_app('DEFAULT_MAP')
	local response
	repeat
		love.timer.sleep(0.01)
		response = live.receive_from_app()
	until response
	local result = {}
	if #response == 0 then
		return result
	end
	return json.decode(response)
end

Definition_background_color = {r=0.7, g=0.7, b=1}

get_definition_from_app = function(name)
	-- return definition for a name
	-- if no such definition, return ''
	live.send_to_app('GET '..name)
	return wait_for_response()
end

		return
	end
	if Move then
		Move.node.x = sx(App.mouse_x()-Move.xoff)
		Move.node.y = sy(App.mouse_y()-Move.yoff)
		A1(Move.node.key)

	elseif Move then
		Move = nil
		A()