basic-menu.py

from collections import deque
import os


def clear():
	os.system('cls' if os.name == 'nt' else 'clear')


clear()

quitCommands = ["quit", "exit", "done", "bye", "leave", "stop"]

menuStack = deque()


def setMenu(obj):
	menuStack.append(obj)
	clear()

	return True


mainMenu = [
	{
		"text": "Print 'Hello!'",
		"command": lambda : print("Hello!")
	},
	{
		"text": "Hack the NSA",
		"command": lambda : print("ffffffffffffffffffffffffffffffffffffffff")
	},
	{
		"text": "Secret menu",
		"command": lambda : setMenu(sub)
	},
]

sub = [
	{
		"text": "Nothing. Don't push me.",
		"command": lambda : print("Told you.")
	},
	{
		"text": "ping",
		"command": lambda : print("pong")
	}
]

menuStack.append(mainMenu)

while (True):
	currentMenu = menuStack[-1]
	canBack = len(menuStack) > 1

	if (canBack):
		print("0.) Previous menu")

	for k, v in enumerate(currentMenu):
		print(f"{k + 1}.)", v["text"])

	print()

	cin = input(">>> ").strip().lower()

	if (cin in quitCommands):
		exit()

	choice = int(cin)

	if ((canBack and choice < 0 or (not canBack and choice < 1)) or choice > len(currentMenu)):
		print("Invalid choice!\n")
		print()

		continue

	if (canBack and choice == 0):
		menuStack.pop()
		clear()

		continue

	print()

	noSpacer = currentMenu[choice - 1]["command"]()

	if (not noSpacer):
		print()