On 2024-03-05, Cameron Simpson via Python-list <python-list@python.org> wrote:
> Because there are no variable definitions in Python, when you write > a function Python does a static analysis of it to decide which > variables are local and which are not. If there's an assignment to a > variable, it is a local variable. _Regardless_ of whether that > assignment has been executed, or gets executed at all (eg in an > if-statement branch which doesn't fire). Unfortunately, crap "information" sites like geeksforgeeks often describe this either incorrectly or so vaguely as to be worthless. >From the page https://www.geeksforgeeks.org/global-local-variables-python/ Python Global variables are those which are not defined inside any function and have a global scope whereas Python local variables are those which are defined inside a function and their scope is limited to that function only. Since "define" (in this context) isn't a term of art in Python, and it's never defined on the page in question, the quoted paragraph is not meaningful: it simply says that "global variables are global and local variables are local". That page goes on to say: In other words, we can say that local variables are accessible only inside the function in which it was initialized This is equally crap. It doesn't matter whether the variable is initialized or not. As Cameron correctly stated, if a function contains an assignment to a variable, and that variable is not declared global, then that variable is local. For example: def foo(): print(s) if 0: s = "there" print(s) In the function above s _is_not_ initialized in the function foo(). However, foo() does contain an assignment to s, therefore s is local unless declared global/nonlocal. [And the first print() will throw an exception even if there is a value bound to the global name 's'.] Unfortunately (presumably thanks to SEO) the enshittification of Google has reached the point where searching for info on things like Python name scope, the first page of links are to worthless sites like geeksforgeeks. -- https://mail.python.org/mailman/listinfo/python-list
