was trying to declare variable t in the first iteration of a recursion

class c:
    def __init__(self, a):
        self.n=a

def a():
    t=c(5)
    def b():
        print(t.n)
    b()

does print t

def d():
    try:
        t
        print(t.n)
    except:
        t=c(5)
        d()

doenst print t

I don't understand the difference and why in the first function does work and the second doesn't

CodePudding user response：

it won't print t because t is a local variable to each function call and is not recognized in the context of the other calls to d. if you want to use it you either have to make it global or pass it as an argument

def d(t=None):
    try:
        print(t.n)
    except:
        t=c(5)
        d(t=t)
d()

More explanation

(There is a great

As you can see in the picture an Infinite number of function calls is made until a stack overflow error happens which leads to the termination of your running program because it never breaks out of the try-except block because each time a function call is made t is defined locally to the function call and make another call which doesn't have t defined in it's scope.