如何访问python3中的上限值？

Question

在JavaScript中，此代码返回4：

let x = 3; let foo = () => { console.log(x); } let bar = () => { x = 4; foo(); } bar();

Answer 1

很明显，程序、机器正在映射工作

bar()

# in bar function you have x, but python takes it as a private x, not the global one
def bar():
  x = 4
  foo()

# Now when you call foo(), it will take the global x = 3 
# into consideration, and not the private variable [Basic Access Modal]
def foo():
   print(x)

# Hence OUTPUT
# >>> 3

现在，如果要打印4，而不是3，这是全局的，您需要在foo（）中传递私有值，并使foo（）接受一个参数

def bar():
  x = 4
  foo(x)

def foo(args):
   print(args)

# OUTPUT
# >>> 4

或

Use global inside your bar(), so that machine will understand that x inside in bar, is global x, not private

def bar():
  # here machine understands that this is global variabl
  # not the private one
  global x = 4
  foo()