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Re: on the order of the const-keyword

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Thiago Adams <thiago.adams@gmail.com> writes:
> On Thursday, October 28, 2021 at 4:56:18 PM UTC-3, Thiago Adams wrote:
> ...
>> > 'const' (as well as short, int, long, float, double, even static and 
>> > typedef) can occur anywhere, in any combination, in the declaration of a 
>> > base type (what goes on the left before the first variable). 
>
> I also have a new definition for typedef considering how it works.
>
> We use to say typedef is a alias for a type name.
>
> But here , 
>
> typedef int Int;
> typedef unsigned Int T; //error
>
> Int does not work as a alias for int.

Yes, it absolutely does.  Given your first declaration, `Int` is an
alias for the *type* `int`, not for the *keyword* `int`.  It's not a
macro, and it doesn't act like one.

The `unsigned` keyword can only be used as the syntax allows, and the
syntax doesn't allow it to be used with a typedef name.  The `unsigned`
keyword can be used by itself as a type name, or along with the `char`,
`short`, `int`, and/or `long` keywords, as defined in N1570 6.7.2.

> So my definition  is:
> when we put typedef in a declaration we declare a variable that has no 
> storage. 

No, that's not what it does.  It doesn't declare a variable at all, with
or without storage, unless you stretch the meaning of "variable" almost
beyond recognition.  (Note that the C standard doesn't use the term
"variable".).  Rather, the `typedef` keyword is treated as a storage
class specifier for syntactic convenience.

> When we use this variable is the same of using typeof(variable) but
> we write just the variable name.
> Int x;
> So typedef is more like "use the same type of that variable here".
>
> considering this.... I was also considering to use typedef to define constants
>
> typedef double pi = 3.14;
> or 
> valuedef double pi = 3.14; 
>
> pi is a non-storage variable, but instead of copying its type
> we copy its initialization value.
>
> double x = pi;

That's more or less what `constexpr` does in C++, and what `const`
*almost* does in C.  Using `typedef` for this would not in my opinion
make sense.

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

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on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-28 12:50 -0300
  Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 17:25 +0100
    Re: on the order of the const-keyword "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-10-28 10:10 -0700
      Re: on the order of the const-keyword Guillaume <message@bottle.org> - 2021-10-28 20:40 +0200
      Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:07 -0300
        Re: on the order of the const-keyword James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-10-29 00:48 -0400
    Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 12:56 -0700
      Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 13:18 -0700
        Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 21:35 +0100
          Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 13:57 -0700
            Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 14:07 -0700
              Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 22:54 +0100
              Re: on the order of the const-keyword Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-28 15:37 -0700
                Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-29 00:02 +0100
        Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-28 22:10 +0100
        Re: on the order of the const-keyword Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-28 15:13 -0700
        Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:40 -0300
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-28 23:48 -0300
  Re: on the order of the const-keyword James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-10-28 13:04 -0400
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:34 -0300
  Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 10:03 +0200
    Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 11:30 +0100
      Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 16:31 +0200
        Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 16:45 +0100
          Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 18:30 +0200
            Re: on the order of the const-keyword Manfred <noname@add.invalid> - 2021-10-30 00:32 +0200
              Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 20:03 -0300
              Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-30 01:10 +0100
            Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 23:51 +0100
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 12:22 -0300
      Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 18:34 +0200
        Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 17:04 -0300

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