Re:Why Hy?
by ashtonbaker on Tuesday May 03, 2022 @11:02AM
(#31249195)
this made me wonder - I know I can use global variables inside a function definition:
so if this 'a' is a new variable, what happens when the name collides with a global variable?
yuck!
[ Parent
| on HN ]
It works if you disambiguate your namespaces:
>>> a = 1
>>> def foo():
... a = globals()['a']
... print(a)
...
>>> foo()
1
Here's another way to do it:
>>> def foo():
... import __main__
... a = __main__.a
... print(a)
...
>>> foo()
1I'm not sure this is so much of a problem? Changing what you name the variable fixes the issue.
Python is generally quite good at having a verbose option to express things, so I'm surprised there's not an explicit way to reference the enclosing scope from an object.
Is there any non-horror piece of code where supporting this latter case would be useful?
It is not a particularly good example. A better one would be
a = 1
def foo():
x = a
a = 2
foo()
> UnboundLocalError: local variable 'a' referenced before assignment
"a = a" just means assign the value of local variable "a" to a local variable "a", so the error makes sense.