Pythonification of the asterisk-based collection packing/unpacking syntax

[Evan Driscoll]

On 12/17/2011 21:42, Chris Angelico wrote:
> Welcome to the list! If you're curious as to what's happened, check
> the archives:
> http://mail.python.org/pipermail/python-list/
Thanks! Incidentally, is there a good way to respond to the original
post in this thread, considering it wasn't delivered to me?

> But [1,2]*2 is operator overloading. The language doesn't quietly
> convert [1,2] into a number and multiply that by 2, it keeps it as a
> list and multiplies the list by 2.
>
> Allowing 1 < True is weaker typing. It should be noted, however, that
> "1 < True" is False, and "1 > True" is also False. The comparison
> doesn't make much sense, but it's not an error.
I see where you're coming from, especially as I wouldn't consider
overloading a function on types (in a language where that phrase makes
sense) moving towards weak typing either. Or at least I wouldn't have
before this discussion... At the same time, it seems a bit
implementationy. I mean, suppose '1' were an object and implemented
__lt__. Does it suddenly become not weak typing because of that?

(The other thing is that I think strong vs weak is more subjective than
many of the other measures. Is '1 < True' or '"1"+1' weaker? I think it
has a lot to do with how the operations provided by the language play to
your expectations.)

On 12/17/2011 22:05, Chris Angelico wrote:
> Not quite; 1 + "one" will be "ne", which might happen to be at memory
> location 2. The data type is going to be char* (or, in a modern
> compiler, const char*), not int. 
I'm not quite sure I'd say that it could be 2, exactly, but I definitely
disagree with this... after running 'int x = 5, *p = &x' would you say
that "p is 5"? (Assume &x != 5.) 1+"one" *points to* "ne", but it's
still a pointer.

Evan



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