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Can global variable be passed into Python function?


On Fri, 28 Feb 2014 09:43:58 +0200, Marko Rauhamaa wrote:

> Chris Angelico <rosuav at gmail.com>:
> 
>> Simple rule of thumb: Never use 'is' with strings or ints. They're
>> immutable, their identities should be their values. Playing with 'is'
>> will only confuse you, unless you're specifically going for
>> introspection and such.
> 
> Here's a use case for "is" with strings (or ints):

I don't think this is a use-case for "is". See below.

>    class Connection:
>        IDLE = "IDLE"
[...]
>        CONNECTED = "CONNECTED"
[...]
>        def disconnect(self):
>            ...
>            if self.state is CONNECTED:
>                ...

Why do you care that the state is *that specific* string, rather than any 
old string with the value "CONNECTED"?

Unless you can explain a good reason why, say, *this* instance 
"CONNECTED" should fail the test, while *that* instance with the same 
value passes, it's not a good use-case for "is".


-- 
Steven