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Re: how/why it is written ... int &numberRef; vs int& numberRef;

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G G <gdotone@gmail.com> wrote:
> my question is why associate the *, or & the the type instead of the 
> name? i do understand it is a preference.

For some reason that I do not know (and possibly nobody does),
when C was originally devised (although it might have come from a
precursor language like B or BCPL, I don't know) they decided that
the indicator for a pointer variable, ie. the asterisk, would be
tied to the variable name rather than the type. In other words,
the asterisk is not, in fact, part of the type at all, but a sort
of indicator that "this variable is a pointer".

This distinction can be seen, as some have pointed out, when declaring
more than one variable in the same expression:

  int *x, *y, z;

Here x and y are pointers, while z is not. The asterisk, the indicator
that means "this is a pointer", is tied to the variable name, not the
type.

Of course this can become a bit confusing when types are used in
contexts other than variable declarations. While C-style typedefs
kind of still follow this principle (as typedef syntax is essentially
just normal variable declaration syntax with just the 'typedef' keyword
added at the very beginning):

  typedef int *IntPtr;

it depends on your point of view whether this is now confusing or not:

  IntPtr ptr;

because now the "this is a pointer" part is part of the type alias,
rather than tied to the variable name.

When a function returns a pointer, it also can become a bit confusing,
if you follow that same convention:

  int *function();

The "this is a pointer" asterisk kind of is part of the return type,
kind of isn't. It's a bit confusing. No wonder many prefer writing
it like this for clarity:

  int* function();

which of course means the exact same thing, but is visually clearer.

And yes, this is valid C (and C++):

  int *function1(), *function2(), function3();

even though it's quite rarely used. (I bet most C/C++ programmers
weren't aware of that.)

C++ makes this even more complicated because there are many more
situations where types are used on their own, without any sort of
variable (or function) name, such as:

  std::vector<int*> vec;

Also here the asterisk kind of is part of the type, kind of isn't.
It's all confusing.

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how/why it is written ... int &numberRef; vs  int& numberRef; G G <gdotone@gmail.com> - 2019-07-12 15:12 -0700
  Re: how/why it is written ... int &numberRef; vs int& numberRef; Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-07-12 23:16 +0100
    Re: how/why it is written ... int &numberRef; vs int& numberRef; G G <gdotone@gmail.com> - 2019-07-12 15:21 -0700
  Re: how/why it is written ... int &numberRef; vs int& numberRef; James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-07-12 18:55 -0400
  Re: how/why it is written ... int &numberRef; vs  int& numberRef; Öö Tiib <ootiib@hot.ee> - 2019-07-12 18:55 -0700
  Re: how/why it is written ... int &numberRef; vs int& numberRef; Szyk Cech <szykcech@spoko.pl> - 2019-07-13 05:33 +0200
  Re: how/why it is written ... int &numberRef; vs  int& numberRef; Juha Nieminen <nospam@thanks.invalid> - 2019-07-15 20:33 +0000
    Re: how/why it is written ... int &numberRef; vs  int& numberRef; Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-07-15 23:03 +0100
      Re: how/why it is written ... int &numberRef; vs  int& numberRef; Öö Tiib <ootiib@hot.ee> - 2019-07-15 18:31 -0700
        Re: how/why it is written ... int &numberRef; vs  int& numberRef; Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-07-16 03:04 +0100
          Re: how/why it is written ... int &numberRef; vs  int& numberRef; Öö Tiib <ootiib@hot.ee> - 2019-07-16 05:59 -0700
        Re: how/why it is written ... int &numberRef; vs int& numberRef; "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-16 05:48 +0200
          Re: how/why it is written ... int &numberRef; vs int& numberRef; David Brown <david.brown@hesbynett.no> - 2019-07-16 08:47 +0200
            Re: how/why it is written ... int &numberRef; vs int& numberRef; "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-16 11:52 +0200
              Re: how/why it is written ... int &numberRef; vs int& numberRef; David Brown <david.brown@hesbynett.no> - 2019-07-16 12:45 +0200
                Re: how/why it is written ... int &numberRef; vs int& numberRef; "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-17 07:06 +0200
                Re: how/why it is written ... int &numberRef; vs int& numberRef; David Brown <david.brown@hesbynett.no> - 2019-07-17 08:17 +0200
                Re: how/why it is written ... int &numberRef; vs int& numberRef; scott@slp53.sl.home (Scott Lurndal) - 2019-07-17 14:03 +0000
          Re: how/why it is written ... int &numberRef; vs int& numberRef; Öö Tiib <ootiib@hot.ee> - 2019-07-16 07:36 -0700
          Re: how/why it is written ... int &numberRef; vs int& numberRef; Juha Nieminen <nospam@thanks.invalid> - 2019-07-17 07:25 +0000
      Re: how/why it is written ... int &numberRef; vs  int& numberRef; Juha Nieminen <nospam@thanks.invalid> - 2019-07-17 07:24 +0000
        Re: how/why it is written ... int &numberRef; vs  int& numberRef; Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-07-17 12:53 +0100

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