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Date: Fri, 3 Jan 2014 16:35:25 +1100
Subject: Re: Ifs and assignments
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:63038

On Fri, Jan 3, 2014 at 3:16 PM, Ethan Furman <ethan@stoneleaf.us> wrote:
> On 01/02/2014 04:06 PM, Chris Angelico wrote:
>>
>>
>> Here's a crazy idea. Suppose we have a "sticky falseness" that can
>> quietly propagate through an expression the way a NaN can... then we
>> could just float that right through the .group() call.
>>
>> class truth:
>
> An interesting idea.  You'd need to add (at least) __getitem__, and I'll
> probably call it `maybe`, myself.  ;)

I was going for something like bool(). If you pass something through
bool(), you get either True or False; if you pass something through
this, you get either itself or something that acts like False.

>> (I'm not sure if I'm using __new__ correctly; I've never actually done
>> it in production code, and the info I found online was mainly Py2
>> examples. Should that be done with super(), or is that applicable only
>> once there's an actual instance with a real MRO?)
>
> I haven't tested it, but your __new__ looks fine.  The only thing you lose
> by not calling super() is the inability for cooperative multiple
> inheritance, except as the ultimate base class.

Is it possible to have multiple inheritance at this point, though? I
get a class argument, not an instance, because there isn't an
instance.

ChrisA