Python scope: “UnboundLocalError: local variable ‘c’ referenced before assignment” [duplicate]

by

Within a function, variables that are assigned to are treated as local variables by default. To assign to global variables, use the global statement:

def g(n):
    global c
    c = c + n

This is one of the quirky areas of Python that has never really sat well with me.

More Related Contents:

  1. Short description of the scoping rules?
  2. UnboundLocalError on local variable when reassigned after first use
  3. Local variables in nested functions
  4. Accessing class variables from a list comprehension in the class definition
  5. Python 3: UnboundLocalError: local variable referenced before assignment [duplicate]
  6. Scope of python variable in for loop
  7. How to access outer class from an inner class?
  8. Why does this UnboundLocalError occur (closure)? [duplicate]
  9. How can I change a global variable from within a function?
  10. How do I pass variables across functions?
  11. Python: load variables in a dict into namespace
  12. Python overwriting variables in nested functions [duplicate]
  13. Python: How can I run eval() in the local scope of a function
  14. How to create module-wide variables in Python? [duplicate]
  15. String with ‘f’ prefix in python-3.6
  16. How to inject variable into scope with a decorator?
  17. How can a function access its own attributes?
  18. globals and locals in python exec()
  19. Does filehandle get closed automatically in Python after it goes out of scope?
  20. Why is one class variable not defined in list comprehension but another is?
  21. Getting “global name ‘foo’ is not defined” with Python’s timeit
  22. How references to variables are resolved in Python [duplicate]
  23. Nested list comprehension scope
  24. Global dictionaries don’t need keyword global to modify them? [duplicate]
  25. Why do I get a `NameError` (or `UnboundLocalError`) from using a named exception after the `except` block?
  26. UnboundLocalError trying to use a variable (supposed to be global) that is (re)assigned (even after first use)
  27. How do the scoping rules work with classes?
  28. Python global variable scoping
  29. Why can functions in Python print variables in enclosing scope but cannot use them in assignment? [duplicate]
  30. Scope of variable within “with” statement?

Leave a Comment