Is 'everything' a refrence or isn't it?

Mike Meyer mwm at mired.org
Sun Jan 15 08:01:43 EST 2006


Steven D'Aprano <steve at REMOVETHIScyber.com.au> writes:
> On Sun, 15 Jan 2006 03:11:27 -0500, Mike Meyer wrote:
>> Steven D'Aprano <steve at REMOVETHIScyber.com.au> writes:
>>> On Sat, 14 Jan 2006 23:26:40 -0500, Mike Meyer wrote:
>>>>> I have no problem with that. Some objects are mutable and can change
>>>>> their value
>>>> If the object *is* the value, how can it change to be a different value
>>>> without also changing to be a diffent object?
>>> Because that's what they do.
>>> Think of it this way: objects are the memory location, the value is the
>>> particular pattern of bits at that memory location. Just because you flip
>>> a couple of bits at location N, changing the value, the location doesn't
>>> change.
>> Ok. So when you say "the object is the value", you're *really* saying
>> "the memory location is the pattern of bits it holds."
> No. You seem to have trouble with analogies. My apologies for not making
> it clearer: I should have said, by analogy, the relationship between
> mutable objects and their value is equivalent to the relationship between
> a memory location and the bit pattern at that location.

No, I don't have any trouble with analogies. I'm just carrying it to
make the point that *I* want to make, rather than stopping at the
point that you want to make.

> It isn't common for programming data to have multiple values
> simultaneously, but it does happen: a certain value can be a pointer to a
> memory location and an integer, or a numeric value and a character.

Yup, and they're all represented by the same bit pattern. I've got no
problem with that.   It's perfectly correct to say that that bit
pattern *is* all those things. On the other hand, it's not correct so
say that the memory location - or the object - that those bit patterns
reside in *is* those those. It isn't - it just holds them.

       <mike
-- 
Mike Meyer <mwm at mired.org>			http://www.mired.org/home/mwm/
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.



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