From: Terje Slettebø (tslettebo_at_[hidden])
Date: 2002-10-14 01:53:11
>From: "Gabriel Dos Reis" <gdr_at_[hidden]>
>Terje Slettebø <tslettebo_at_[hidden]> writes:
>| >From: "Daniel Frey" <daniel.frey_at_[hidden]>
>| >>Gabriel Dos Reis wrote:
>| >> | To me, it is something that I can read.
>| >> Interesting. So you can read a reference. How?
>| >I knew it was going in the wrong direction :) I mean the sematic of
>| >"value" against the semantic of "object". I don't refer to the standard
>| >here, but to the meaning of these words in the natural language (of a
>| >C++ programmer :).
>| I think the discussion could be clearer if "lvalue" or "rvalue" is used,
>| instead of "value" and "object". An object is a value. See e.g. 3.10,
>| "Lvalues and rvalues".
>Note however that the definitions found in 3.10 aren't really helpful
>in distinguishing lvalues from rvalues. Just look at the footnote to get
>some feeling :-)
I know. :) I've seen a long discussion of lvalue and rvalue, earlier.
However, I thought it could be a more useful distinction than "value" and
"object". 42 is also a literal, as has been pointed out.
>I think the whole thing would have been clearer if the notion of
>lvalue were refelected at the type-system level.
>| >> | It's different from an "object", which is something you can change.
>| >An example: 42 is a value.
>| Yes, an rvalue.
>| >An 'int' which holds the value 42 is an
>| >"object", as you can modify it.
>| And that's an lvalue.
>That is not clear: int(42) designates an object; and at the same time,
>it is an rvalue (according to the standard).
Yes. I took "int" here to mean an int variable.
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