Can global variable be passed into Python function?

[Steven D'Aprano]

On Sat, 01 Mar 2014 19:29:41 +0200, Marko Rauhamaa wrote:

> Michael Torrie <torriem at gmail.com>:
> 
>> No, '==' works fine no matter what objects you assign to your state
>> variables.
> 
> Well, it doesn't since
> 
>    >>> a = float("nan")
>    >>> a is a
>    True
>    >>> a == a
>    False

No, that is working correctly, so the comment that equals works fine is 
correct: returning False is the correct thing to do if one or both of the 
objects are a NAN. NANs are supposed to compare unequal to everything, 
including themselves.

The is operator and the == operator do not have the same purpose and they 
do not do the same thing. "is" should not be considered an improved == 
without the quirks, this is not PHP and we're not comparing == and ===. 
The argument here is not about which operator performs the check we want, 
but over what check we want: do we want an identity test or an equality 
test?



-- 
Steven D'Aprano
http://import-that.dreamwidth.org/