Global variable declaration

[psbasha]

Is there any declaration or defintion has to be done in the Sample1 and Sample2 modules?


- PSB

[bartonc]

The mutable type to use between modules would be a class:

# test.py
# class holds globals

import inspect # just for testing this idea

def PrintGlobRep():
    for member in inspect.getmembers(globRep):
        if not member[0].startswith('_'):
            print member

class GlobalRepository:
    globalList = []
    globalInt = 5


globRep = GlobalRepository()

That last line is special. It creates the global repository when the import is executed. It is accessed below by "from module import1". This is the best way to bring a mutable type variable for one module to another. Generally, though, this is done for "constants" (variables that should NEVER be assigned to).

# module1.py

# module1 uses Global Repository from test.py

import test # this does initialization of the Global Repository
from test import globRep # get the class instance

test.PrintGlobRep()
globRep.newGlobal = 12
test.PrintGlobRep()

('globalInt', 5)
('globalList', [])
('globalInt', 5)
('globalList', [])
('newGlobal', 12)

[psbasha]

Usually "global" variables in any programming languages are used very rarely, and as Barton said,we dont know where the value of the global value be changed.It will be very difficult to track the value of it.

"global" variable main purpose is to make the life of the variable available from begining to the last of the program.

Thanks
PSB

[bartonc]

Usually "global" variables in any programming languages are used very rarely, and as Barton said,we dont know where the value of the global value be changed.It will be very difficult to track the value of it.

"global" variable main purpose is to make the life of the variable available from begining to the last of the program.

Thanks
PSB

That makes sense. Other options include database, config file, windows registry, etc. I uese the registry for startup values and SQL databse for shrare values.

[psbasha]

I tried as you suggested ,but still I am not able to solve the problem.

Suggest me the location where I have to change in my sample code.

Main.py
from Sample1 import CSample1
from Sample2 import CSample2
from Sample1 import iVar
from Sample2 import iVar

iVar = 1
if __name__ == '__main__':
  
    
    obj1 = CSample1()
    obj2 = CSample2()

    obj1.Func1()
    obj2.Func4()
    print iVar

Sample1.py
class CSample1:

    def Func1(self):
        global iVar
        iVar = 20
        
        print iVar
    
    def Func2(self):
        pass
    
iVar = CSample1()

Sample.2py
class CSample2:

    def Func3(self):
        pass
    
    def Func4(self):
        global iVar
        print iVar

iVar = CSample2()

-PSB

[psbasha]

I tried as you suggested ,but still I am not able to solve the problem.

Suggest me the location where I have to change in my sample code.

Main.py
from Sample1 import CSample1
from Sample2 import CSample2
from Sample1 import iVar
from Sample2 import iVar

iVar = 1
if __name__ == '__main__':
  
    
    obj1 = CSample1()
    obj2 = CSample2()

    obj1.Func1()
    obj2.Func4()
    print iVar

Sample1.py
class CSample1:

    def Func1(self):
        global iVar
        iVar = 20
        
        print iVar
    
    def Func2(self):
        pass
    
iVar = CSample1()

Sample.2py
class CSample2:

    def Func3(self):
        pass
    
    def Func4(self):
        global iVar
        print iVar

iVar = CSample2()

-PSB

I am getting the following output

>>>
20
<Sample2.CSampl e2 instance at 0x00CF65F8>
1
>>>

[psbasha]

Any suggestions on the above posting.

-PSB

[bvdet]

Any suggestions on the above posting.

-PSB

# Main.py
try:
    reload(Sample1)
except:
    import Sample1
    
try:
    reload(Sample2)
except:
    import Sample2

iVar = 1
if __name__ == '__main__':
  
    
    obj1 = Sample1.CSample1()
    obj2 = Sample2.CSample2()

    print iVar
    iVar = obj1.Func1()
    print iVar
    iVar = obj2.Func4()
    print iVar

# Sample1.py
class CSample1:

    def Func1(self):
        iVar = 40
        return iVar
    
    def Func2(self):
        pass

# Sample.2py
class CSample2:

    def Func3(self):
        pass
    
    def Func4(self):
        iVar = 20
        return iVar

>>> 1
40
20
>>>

It seems like a lot of trouble though.

[psbasha]

Thanks for the reply

Is it not possible to get the results using the 'global'key word in different module?

-PSB

[bvdet]

Thanks for the reply

Is it not possible to get the results using the 'global'key word in different module?

-PSB

Yes.

try:
    reload(Sample1)
except:
    import Sample1
    
try:
    reload(Sample2)
except:
    import Sample2

iVar = 1
if __name__ == '__main__':
  
    
    obj1 = Sample1.CSample1()
    obj2 = Sample2.CSample2()

    print iVar
    iVar = obj1.Func1()
    print iVar
    iVar = obj2.Func4()
    print iVar
    print Sample1.iVar

# Sample1.py
class CSample1:

    def Func1(self):
        global iVar
        iVar = 40
        return iVar
    
    def Func2(self):
        pass

a =  CSample1()
a.Func1()

>>> 1
40
20
40