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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: A string pointer to a static or dynamic string : how to free the dynamic one ?
Date: Sun, 22 Jan 2023 13:07:51 -0800
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"R.Wieser" <address@not.available> writes:
> "Richard Damon" <Richard@Damon-Family.org> wrote in message 
> news:sbfzL.383809$iU59.50359@fx14.iad...
>> On 1/22/23 9:40 AM, R.Wieser wrote:
>>> If an address which is pointing to a sequence of characters is called a 
>>> "pointer to a string" - normally referred to as "a string pointer" - , 
>>> what should the variable which stores that addres be called ?
>>
>> A pointer to string (with type pointer to char).
>
> Yep. Both referred to with the exact same name.  And that confuses the h*ll 
> outof someone who has to listen to someone talking about two different 
> things, but uses the same word for both. :-(
>
> Why do you think I asked ?
>
>> If you need to distinguish them, one is a value, and the other is a 
>> variable
>
> You know that, I know that.  But listening to people talking about both 
> using the same "string pointer" name I have to wonder if they do ...

If I understand you correctly, the two things you're referring to are
the pointer *value* and an *object* of pointer type that holds that
value.

There's nothing special about pointers to strings here.  The same
confusion occurs with, for example, a pointer to an int (which is
convenient, because we can discuss this without dragging C into the
discussion).

    int n = 42;
    int* ptr = &n;

The result of evaluating the expression `&n`, or the expression
`ptr`, is a value of type `int*`.  We commonly refer to this value as
"a pointer" (or "an address").

The object named `ptr` is an object (variable) of type `int*`.
We also commonly refer to this object as "a pointer" (though not as
"an address").

Similarly we can refer either to `42` or to the object `n` as
"an integer" or "an int".

Usually this isn't a problem.  In most contexts, the distinction
between a value of some type and an object/variable that holds a
value of some type either isn't important or is sufficiently clear
from the context.

For cases where the ambiguity is important, I find it useful
to think of the word "pointer" (as well as "array", "integer",
etc.) as an adjective rather than a noun.  Thus we can refer to a
*pointer value*, or a *pointer object", or a *pointer type*, or a
*pointer expression*, all of which are clearly distinct concepts.
I'll note that the C and C++ standards often do not use this level
of precision (and in most cases they probably don't need to).

<OT>
For C's definition of a "pointer to a string", I'd say it refers
to a *value* of pointer type.  An object of type char* might have a
current value that is a pointer to a string, but then after a value
is assigned to it it might not.  The state of being a "pointer to
a string" applies to the value, not to the object that currently
happens to hold such a value.

I don't recall seeing a use of the term "pointer to a string" that
was confusing because it could refer to either a value or an object.
</OT>

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for XCOM Labs
void Void(void) { Void(); } /* The recursive call of the void */