Re: Local variables to a function doesn't disapear after function execution. Why ?

[ast]

"Christian Gollwitzer"  a écrit dans le message de 
news:ntl6in$on5$1...@dont-email.me...

Am 12.10.16 um 13:18 schrieb ast:


Because the Test() call does never terminate. You have the mainloop inside of your constructor. As 
long as this loop runs, your program exists. Try it by putting


test=Test()
print("Now I am here")

and you'll see.

Christian


Ah yes, mainloop() is an endless loop.
Thanks 


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Re: Local variables to a function doesn't disapear after function execution. Why ?

[Christian Gollwitzer]

Am 12.10.16 um 13:18 schrieb ast:

Hello, here is the small program:

from tkinter import *

class Test:
   def __init__(self):
   root = Tk()
   label = Label(root, text="this is a test")
   label.pack()
   root.mainloop()

test=Test()

I dont understand why this program works. After execution
of function __init__, local variables 'root' and 'label' should disapear
and the widgets Tk and Label should be garbage collected. But it's not
the case, the window Tk is still on the screen with the label inside it.
Why ?



Because the Test() call does never terminate. You have the mainloop 
inside of your constructor. As long as this loop runs, your program 
exists. Try it by putting


test=Test()
print("Now I am here")

and you'll see.

Christian
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