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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: C++ features for C
Date: Sat, 12 May 2018 15:53:34 -0700
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bartc <bc@freeuk.com> writes:
[...]
> & works with a normal variable, because when you write:
>
>    double x;
>
> then the type of 'x' - the name, not the contents of the location it 
> refers to - is really double*. When used in an expression, it is 
> automatically dereferenced to yield the contents of the location:
>
>     *(&x);        // equivalent to just x in a HLL
>
> When you write &x, then that is really this:
>
>     &*(&x);
>
> The & and * cancel to leave you with &x, of type double*.

"That's not how this works.  That's not how any of this works."

The object named `x` is of type double.  The definition `double x;` does
not create anything of type `double*`, any more than it creates anything
of type `size_t`.

The *expression* `&x` is of type `double*`.  That value, of pointer
type, doesn't exist until the expression `&x` is evaluated.  Similarly,
`sizeof x` is of type size_t, and that value doesn't exist until the
expression `sizeof x` is evaluated.

An lvalue is an expression that "designates" an object.  That is not at
all the same thing as a *pointer* to an object.

[...]

> This why I think few people 'get it'; they certainly don't get the need 
> for an ultra-simple feature with straightforward rules.

You should understand the existing rules before proposing new ones.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"