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Re: qualified rvalues

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Jens Gustedt <jens.gustedt@loria.fr> wrote:
> 
> In essence I didn't find that the standard has much to say when it
> comes to qualified types for rvalues. They definitively do exist,
> since the cast operator explicitly specifies that the type could be
> qualified. The section on casts also has the only indication I found
> that relates to rvalues. There is a footnote (thus not normative) that
> says
> 
>  > 89) A cast does not yield an lvalue. Thus, a cast to a qualified
> > type has the same effect as a cast to the unqualified version of the
> > type.

The other relevant passages are 6.7.3p4:

	The properties associated with qualified types are meaningful
	only for expressions that are lvalues.

(which is the justification for the above footnote [104 in C11]), and
6.3.2.1p2:

	Except when it is the operand of the sizeof operator, the unary
	& operator, the ++ operator, the -- operator, or the left
	operand of the . operator or an assignment operator, an lvalue
	that does not have array type is converted to the value stored
	in the designated object (and is no longer an lvalue); this is
	called /lvalue conversion/. If the lvalue has qualified type,
	the value has the unqualified version of the type of the lvalue;

> That could mean two things:
> 
> (1) the effective type of the resulting rvalue is unqualified
> (2) all operators that will accept the rvalue as an operand will act
>     all the same whether the type is qualified or not

Based on the above, I believe that (1) was what the committee intended.
-- 
Larry Jones

Who, ME?  Who?! Me??  WHO... Me?!  Who, me??? -- Calvin

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qualified rvalues Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-23 15:28 +0200
  Re: qualified rvalues lawrence.jones@siemens.com - 2012-06-23 17:31 -0400
    Re: qualified rvalues Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-24 01:09 +0200

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