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Subject: Re: Values of objects
From: Hyman Rosen (hyrosen_at_[hidden])
Date: 2019-08-28 14:05:19


On Wed, Aug 28, 2019 at 2:53 PM Krystian Stasiowski via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> > The right way to define this is to say that objects have a value
> representation consisting
> of a fixed subset of the bits of their object representation, and that the
> value of an object
> is the sequence of bits in the value representation.
>
> Not quite, while the value representation of an trivially copyable type
> will appear in the object representation, for an object of non-trivially
> copyable type, the value is a user established thing: such as
> `std::string`, since it has a pointer to external data.
>

Not not quite. Pick your own words if you want, but we should have one word
for the contents of the value representation and another for the
"user-established
thing". I like "same" for the former and "equal" for the latter, so two
std::string
objects are the same if they point to the same external data (makes more
sense
for string views), and are equal if they point to identical sequences of
characters.



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