submit_definition = function(State)
	-- TODO: don't hang if you lose connection to client app here
	-- always clear error on 'F4'
	State.load_time_error = nil
	if empty_editor(State) then
		return
	end
	-- send definition to app and check for any load-time errors
	live.send_definition_to_app(State)
	local response = wait_for_response()
	Client_app_test_failures = json.decode(response)
	if Load_time_error then
		State.load_time_error = Load_time_error
		Load_time_error = nil
	end
	-- wait a little (~0.1s) for any immediate run-time errors
	for i=1,10 do
		if live.receive_run_time_error_from_app() then
			break
		end
		love.timer.sleep(0.01)
	end
	-- now both errors likely to be available to on.code_submit
	if on.code_submit then on.code_submit(State) end
end