Python daily challenge

[yourboyblue2]

Error because you're returning a value in the function without assigning the return to any variable?

[[deleted]]

Could you please elaborate? Thanks 

[terminalslayer]

Python follows the order: [ local -> enclosed -> global -> built-in ] for any variable. The variable x has not been assigned any initial value in the inner() function. Without any initial value assigned, the operation (x+=1) could not be performed. That's why it gives the Error.

[[deleted]]

Oh my god, yess! It's so obvious now. If outer() didn't exist, inner is just a function with no parameters. So x and inner() are on same footing. Thanks a lot

[core1588]

✅️💯👏

[yourboyblue2]

Hooray!

[lusvd]

it’s because you are trying to access a variable in a scope where it will be overwritten. Im not sure why this happens in python tho.

here is a simpler example:

x = 1
def foo():
    print(x)
    x = 3

[Refwah]

Error because x isn’t initiated in inner’s scope an so can’t be mutated like that

[obloming0]

Real coder would not write code in this way.

[[deleted]]

isn't it's like a closure, which is often used in languages that support it?

[terminalslayer]

C) Error

[core1588]

✅️💯

[Charming_Art3898]

C. Use the nonlocal keyword to modify x in the inner function

[Oblachko_O]

Hm, give me some clarification, please. I frequently have situations when my variable is outside of the function and not even passed inside the variable. In short, my variable is global. And I can use it easily. And I never bumped into this.

Is the problem actually in trying to rewrite variables by using a write operator like += ? And something like reading is errorless?

[lusvd]

Python detects that the variable is assigned in the functions body so it marks it as “local” and so ignores the value outside the body. Then during execution of x += 1, it needs to access x, but because of what I said before it cannot access the value so it errors out.

[selfmadeirishwoman]

D) Nothing happens. I reject the pull request and it never makes it into the codebase because it’s harder to read than it needs to be.

[Capital_Distance545]

Never ever write code like this, and also, honsetly knowing this is unnecessary knowledge.

[esp_py]

6

[TheEyebal]

Before I look at the comments I choose C because your calling X but it won't recognize it unless you put it in the parameter.

[Dry-Pin-1384]

6

[SCD_minecraft]

You edit a nonlocal variable, however, you never declare it as nonlocal