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Re: Const-qualified function return type in C - is it a part of function type?

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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

> luser droog <luser.droog@gmail.com> writes:
>
>> On Saturday, February 22, 2020 at 8:22:18 AM UTC-6, Ben Bacarisse wrote:
>>
>>> Andrey Tarasevich <andreytarasevich@hotmail.com> writes:
>>> <cut>
>>>
>>>> To avoid any further wastage of time on this irrelevant matter I
>>>> hereby postulate one more time:  the above quoted passage refers to
>>>> qualifiers applied to the function type itself (which, BTW, is only
>>>> possible through typedef names).
>>>
>>> And interesting detail, which I can't interpret...  In all versions of
>>> the C standard, there is a footnote attached to the paragraph
>>>
>>>   "If the specification of an array type includes any type qualifiers,
>>>   the element type is so qualified, not the array type.  If the
>>>   specification of a function type includes any type qualifiers, the
>>>   behavior is undefined."
>>>
>>> In C90, this footnote seems to be:
>>>
>>>   59) Both of these can only occur through the use of typedefs.
>>>
>>> By C99 it appears to have become
>>>
>>>   118) Both of these can occur through the use of typedefs.
>>>
>>> Why the change I wonder?  Is there a way to qualify a function or array
>>> type without a typedef?  I can't see one.
>>
>> What about using parens?
>
> I don't think you can.  I tried.

I concur with Ben here.

>> int (const sammy[2]);
>
> I think int (const sammy)[2]; would be closer (were it allowed) because
> parentheses in a declarator are there to stop you reading in the
> "default" direction -- to the right.  Reading what you wrote, you'd say
> "sammy is an array of 2 const int".
>
>> float (volatile davis)(void);
>
> That's the way it would be written, but you can't do that as far as I
> can see.

If we are looking for an extension to supply the capability, how
about this way:

    int sammy const [2];
    float davis volatile (void);

I note with some amusement that C++ made a different choice, for
member functions:

    int x_value() const;

Of course the meaning of "const" here isn't quite the same as
the "const" we are used to, but it does modify the function
type itself:  they are commonly (or officially?) called
"const member functions".

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Const-qualified function return type in C - is it a part of function type? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2020-02-21 14:35 -0800
  Const-qualified function return type in C - is it a part of function type? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-21 15:24 -0800
    Re: Const-qualified function return type in C - is it a part of function type? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2020-02-21 16:19 -0800
      Re: Const-qualified function return type in C - is it a part of function type? Richard Damon <Richard@Damon-Family.org> - 2020-02-21 20:50 -0500
        Re: Const-qualified function return type in C - is it a part of function type? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2020-02-21 19:56 -0800
          Re: Const-qualified function return type in C - is it a part of function type? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-22 14:22 +0000
            Re: Const-qualified function return type in C - is it a part of function type? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 10:06 -0800
              Re: Const-qualified function return type in C - is it a part of function type? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-22 21:20 +0000
                Re: Const-qualified function return type in C - is it a part of function type? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-24 20:58 -0800
            Re: Const-qualified function return type in C - is it a part of function type? luser droog <luser.droog@gmail.com> - 2020-02-22 19:24 -0800
              Re: Const-qualified function return type in C - is it a part of function type? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-23 03:52 +0000
                Re: Const-qualified function return type in C - is it a part of function type? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-24 21:06 -0800
      Re: Const-qualified function return type in C - is it a part of function type? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-02-21 21:21 -0800
  Re: Const-qualified function return type in C - is it a part of function type? Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-22 07:51 +0100
    Re: Const-qualified function return type in C - is it a part of function type? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2020-02-22 05:00 -0800
      Re: Const-qualified function return type in C - is it a part of function type? Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-22 16:23 +0100
      Re: Const-qualified function return type in C - is it a part of function type? Guillaume <message@bottle.org> - 2020-02-22 20:37 +0100
        Re: Const-qualified function return type in C - is it a part of function type? Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-22 20:50 +0100
          Re: Const-qualified function return type in C - is it a part of function type? David Brown <david.brown@hesbynett.no> - 2020-02-23 07:29 +0100
            Re: Const-qualified function return type in C - is it a part of function type? Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-23 08:57 +0100
  Re: Const-qualified function return type in C - is it a part of function type? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 09:53 -0800

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