Scope of variables in Python methods with identical default parameters?

Question

After a good bit of searching i couldn’t find any examples covering this. But i might not be using the correct terminology, since im confused about the situation, and what to even ask if that makes sense? So i feel like this is a duplicate probably.

But if you have a Python class, with two methods that have a parameter that has the same name, whats the behaviour of this?

class Foo():

    def __init__(self, arg1=1, arg2=2):

    def methodOne(self, amount, setting=None, extra=0):         

    def methodTwo(self, amount, setting=None):
        ...
        #What is going on with setting here? What is setting referring to?
        self.methodOne(amount, setting=setting)

@John1024 self is defined in the code im looking at, forgot to put that, ive updated question. — 9fpqhijf7zm1qrgn760r2hzipi92n7
– 9fpqhijf7zm1qrgn760r2hzipi92n7, Commented Aug 11, 2014 at 2:49

Ignacio Vazquez-Abrams · Accepted Answer · 2014-08-11 02:31:28Z

1

The setting on the left can only be referring to a keyword argument, and the setting on the right can only be referring to a name. That's how Python's parser works.

answered Aug 11, 2014 at 2:31

Ignacio Vazquez-Abrams

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6 Comments

9fpqhijf7zm1qrgn760r2hzipi92n7 Over a year ago

I forgot to add self in my question, as the code im looking at has self defined, now it matches up, so maybe that changes your answer?

Ignacio Vazquez-Abrams Over a year ago

No. The Python parser does not change.

9fpqhijf7zm1qrgn760r2hzipi92n7 Over a year ago

Ahh okay, well in that case, im still not understanding lol. What do you mean by "keyword argument" and "name"?

Ignacio Vazquez-Abrams Over a year ago

docs.python.org/2/tutorial/controlflow.html#keyword-arguments docs.python.org/2/tutorial/…

9fpqhijf7zm1qrgn760r2hzipi92n7 Over a year ago

Okay so in self.methodOne(amount, setting=setting) , the second argument is a keyword argument? And you just happen to be passing the value setting? Just as well it could be something like self.methodOne(amount, setting='no')? I think i understand now.

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