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Sys module - Uchikago - Jul-11-2019
can any body explain why this didn't work
#test1.py
var=99
def glob3():
var=0
import sys
glob=sys.modules['test1']
glob.var+=1
glob3()
print(var) #python report an errorBut when i import that test1 module in interactive prompt, it worked: >>> import test1 100
RE: Sys module - Gribouillis - Jul-11-2019
Because when you run the file without importing it, the variable
__name__ has value '__main__' instead of 'test1' and the module is sys.modules['__main__']. You could useglob = sys.modules[__name__]However, this is strange python code. Why do you want to do this?
RE: Sys module - Uchikago - Jul-11-2019
(Jul-11-2019, 05:17 AM)Gribouillis Wrote: Why do you want to do this?I'm just experimenting alternative way to use global variable
RE: Sys module - Gribouillis - Jul-11-2019
Uchikago Wrote:I'm just experimenting alternative way to use global variableThe best way is not to update global variables from functions. On the other hand, global variables can be mutable objects such as dictionaries or lists. This way you don't need the global statement.