Python local and global variable

Question

def f():
    global s
    print s
    s = "That's clear."
    print s     

s = "Python is great!" 
f()
print s

Output:

Python is great!
That's clear.
That's clear.

as per program, the last print statement should return "s= Python is great" because I think here S should be referred Global variable.

It is, but you gave it a new value in `f()`. Globals can be accessed and modified in any scope. If you want the last print to output "Python is great", then you should *not* declare `s` a global. — stelioslogothetis, Jul 13 '17 at 10:26
No, you just updated it in your function. It would still be "Python is great!" if you hadn't declared it as global in f. — Thierry Lathuille, Jul 13 '17 at 10:26
You have changed the value of global variable 's' in the function 'f()' — Albin Antony, Jul 13 '17 at 10:36

score 2 · Answer 1 · answered Jul 13 '17 at 10:28

2

You modified the global variable in your function (f) so the variable now has the value that you modified at last i.e. "That's clear."

answered Jul 13 '17 at 10:28

Nimish Bansal

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score 0 · Accepted Answer · answered Jul 13 '17 at 10:42

The output is correct. After s is defined as a global variable, you print the value assigned to s at that point which is Python is great, then you assign That's clear. to s - s is now global, so when you assign That's clear. to it inside your function, that becomes it's value in the outer scope as well.

Here is a good stackoverflow answer regarding Scoping Rules.

Python local and global variable

2 Answers2