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Re: what is data type 'int *' ?

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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
> Richard Heathfield <rjh@cpax.org.uk> writes:
> <snip>
>>    ptr = &var;
>
> <snip>
>
>> Secondly, the types on either side of an assignment statement must
>> match. They need not always be exactly the same type, but the types must
>> be "compatible". In this case, there is no problem matching the types,
>> as we shall see.
>
> Just a small point: the types need not be compatible.  You put the term
> in scare quotes but whether that marks the term as simply being "jargon"
> or "not quite the right word" is not always clear.

To expand on that, two type are "compatible" if they're the *same type*,
or in a few other limited circumstances specified in several different
part of the standard.  For example, none of the types char, signed char,
and unsigned char are "compatible" with each other, even though char is
guaranteed to have exactly the same representation as one of the other
two.  int and long are not compatible even if they have the same size.

> It's a shame that there is no term for the relationship between types
> that are "close enough for assignment".  It's far too useful a concept
> not to have a technical name.

I refer to such types as "implicitly convertible".  For example, all
arithmetic types are implicitly convertible.  The same rules apply to
simple assignment, argument passing, and initialization.

-- 
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"

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what is data type 'int  *' ? bilsch <king621@comcast.net> - 2015-02-04 23:45 +0000
  Re: what is data type 'int  *' ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-05 00:09 +0000
    Re: what is data type 'int  *' ? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-02-05 01:24 +0000
      Re: what is data type 'int  *' ? James Kuyper <jameskuyper@verizon.net> - 2015-02-05 07:00 -0500
        Re: what is data type 'int  *' ? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-02-05 14:09 +0000
          Re: what is data type 'int  *' ? Robert Wessel <robertwessel2@yahoo.com> - 2015-02-05 13:08 -0600
            Re: what is data type 'int  *' ? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-02-06 00:33 +0000
              Re: what is data type 'int  *' ? Robert Wessel <robertwessel2@yahoo.com> - 2015-02-05 19:30 -0600
                Re: what is data type 'int  *' ? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-02-06 10:17 +0000
                Re: what is data type 'int  *' ? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-02-07 13:21 -0800
  Re: what is data type 'int  *' ? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-02-04 19:47 -0500
    Re: what is data type 'int  *' ? bilsch <king621@comcast.net> - 2015-02-05 09:40 +0000
      Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 09:51 +0000
    Re: what is data type 'int  *' ? Keith Thompson <kst-u@mib.org> - 2015-02-05 08:04 -0800
      Re: what is data type 'int  *' ? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-02-06 00:42 +0000
        Re: what is data type 'int  *' ? Keith Thompson <kst-u@mib.org> - 2015-02-05 19:09 -0800
  Re: what is data type 'int  *' ? Kaz Kylheku <kaz@kylheku.com> - 2015-02-05 01:17 +0000
  Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 03:04 +0000
    Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 03:06 +0000
  Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 03:06 +0000
    Re: what is data type 'int  *' ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-05 10:20 +0000
      Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 10:47 +0000
        Re: what is data type 'int  *' ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-05 12:18 +0000
          Re: what is data type 'int  *' ? Richard Heathfield <rjh@cpax.org.uk> - 2015-02-05 12:40 +0000
      Re: what is data type 'int  *' ? Keith Thompson <kst-u@mib.org> - 2015-02-05 08:24 -0800
        Re: what is data type 'int  *' ? James Kuyper <jameskuyper@verizon.net> - 2015-02-05 11:42 -0500
        Re: what is data type 'int  *' ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-02-05 17:13 +0000
    Re: what is data type 'int  *' ? Keith Thompson <kst-u@mib.org> - 2015-02-05 08:43 -0800
  Re: what is data type 'int  *' ? bilsch <king621@comcast.net> - 2015-02-05 09:45 +0000
  THANKS FOR THE INFO bilsch <king621@comcast.net> - 2015-02-05 09:47 +0000

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