How to share global variables between files in Python like C

Question

i have 2 files

#foo.py
 global x
 def foo():
   x = 8


#main.py
from conf import *

 if __name__ == "__main__":
 foo()

how to get the X value in main.py file i have to use only 2 files here now if print or store x to other variable it has to print 8

`foo` is not assigning to a global `x`, since it does not define `x` to be global. The `x` within `foo` is local to `foo`. To make it global, it needs to be declared global inside the function, not outside of it. Move the global declaration to be inside of `foo`. — Tom Karzes, Jun 03 '20 at 14:23
For starters, you have to put some form of `input foo` in `main.py`. Or is `conf` a typo for `foo`? — chepner, Jun 03 '20 at 14:28
Well, that's only part of the problem. Try changing the import to `import foo`, then you can do `foo.foo()` and then examine `foo.x` and you should see it, provided it's global (which in the posted code it is not). — Tom Karzes, Jun 03 '20 at 14:28
@Yashvanth It doesn't give errors. I'm assuming the file name is `foo.py`. I don't know what `conf.py` is. If you have `foo.py`, then `import foo` should work. If you can't get that much to work, then you have much more basic problems than accessing global variables. — Tom Karzes, Jun 03 '20 at 15:07

score 0 · Accepted Answer · answered Jun 03 '20 at 14:36

0

You can do something like this to get varaible x in main.py , if you declare x as global inside foo() that mean you will be accessing the global x not local x.

#foo.py
 x =10
def foo():
   x = 8
   print(" in foo x= " ,x)


#main.py
from conf import *
from foo import x, foo

if __name__ == "__main__":
   print(" x imported from foo.py  = ", x)
   foo()

OUTPUT

x imported from foo.py  =  10
in foo x=  8

answered Jun 03 '20 at 14:36

Thomas Lazer

178
6

from foo import x, foo ModuleNotFoundError: No module named 'foo' i got this error – jack sparrow Jun 03 '20 at 14:43
I can run this code successfully on my machine , make sure foo.py and main.py are in same folder – Thomas Lazer Jun 03 '20 at 14:46
but the i need x value 8 not 10 – jack sparrow Jun 03 '20 at 14:50
then you should use simply add a `return x` statement in `foo()` and in main.py call foo as `somevariable = foo()` and now this some variable will be the value of x i.e 8 and you can use it any where in youe main.py – Thomas Lazer Jun 03 '20 at 14:55
but if have to access more then one variables in foo function like x = 8 and y =15 in this seniority what will be solution – jack sparrow Jun 03 '20 at 14:58
In python you can return more than one , `return x, y ` or you can return a list with number of variables :) – Thomas Lazer Jun 03 '20 at 15:05
and in main.py `somex, somey = foo` , Plz accept and upvote if it helped – Thomas Lazer Jun 03 '20 at 15:08

omar · Answer 2 · 2020-06-04T01:53:36.087

0

you have to use the global keyword properly

# foo.py
x = None

def foo():
    global x
    x = 8

#main.py
# this imports everything from foo in main
from foo import *

if __name__ == "__main__":
foo()
print(x)

edited Jun 04 '20 at 01:53

answered Jun 03 '20 at 14:39

omar

190
1
10

how to access the x value in main.py files – jack sparrow Jun 03 '20 at 14:44
you imported everything from foo with * wildcard so you can access it normally in main.py. just do print(x) – omar Jun 04 '20 at 01:51

How to share global variables between files in Python like C

2 Answers2