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Re: Compound types as functions in latest C++ standard

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On 2011-05-03 15:32:00 -0400, Edward Diener said:

On 5/2/2011 3:10 PM, Francis Glassborow wrote:
>
>
>> On 01/05/2011 19:52, Edward Diener wrote:
>>
>>
>>> In the latest C++ standard document (n3290) in section 3.9.2 part 1,
>>> where it mentions the ways in which compound types can be constructed
>>> I read:
>>>
>>> "=97 functions, which have parameters of given types and return void or
>>> references or objects of a given type, 8.3.5;"
>>>
>>> Should not this say "... return void or references or pointers or
>>> objects of a given type, 8.3.5;", or better yet just say "... return
>>> void or given types, 8.3.5;".
>>>
>>>
>>> Strictly speaking a pointer is an object. References are not objects. A
>>>
>> function does not and cannot return a type. So the wording is correct as
>> it stands.
>>
>>
> I did not realize that "a pointer is an object" in C++ standards
> terminology. In that case the original wording is perfectly correct.
>
> I do think it is natural to have assumed that "an object" meant something
> different. One often refers to "pointers to objects" or "references to
> objects" to distinguish objects themselves from the pointer or reference
> wa=
> y
> of specifying an object.
>

"object" as it's used in the standard is a compiler writer's term, not an
object-oriented programming term. An object is a region of storage and the
operations that are associated with it. So a pointer to an object is an
object, and, recursively, a pointer to a pointer to an object is also an
object. Since a reference doesn't have memory associated with it (although
it may be a pointer under the hood), it isn't an object; further, there are
no operations on references, only operations on the thing that's referred
to, so it isn't an object.

-- 
 Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference (
www.petebecker.com/tr1book)


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Compound types as functions in latest C++ standard Edward Diener <eldiener@tropicsoft.invalid> - 2011-05-01 12:52 -0600
  Re: Compound types as functions in latest C++ standard Francis Glassborow<francis.glassborow@btinternet.com> - 2011-05-02 13:10 -0600
    Re: Compound types as functions in latest C++ standard Edward Diener <eldiener@tropicsoft.invalid> - 2011-05-03 19:32 -0600
      Re: Compound types as functions in latest C++ standard  Pete Becker <pete@versatilecoding.com> - 2011-05-04 12:46 -0600
  Re: Compound types as functions in latest C++ standard Daniel Krügler<daniel.kruegler@googlemail.com> - 2011-05-02 13:10 -0600
  Re: Compound types as functions in latest C++ standard Johannes Schaub<schaub.johannes@googlemail.com> - 2011-05-02 13:11 -0600
    Re: Compound types as functions in latest C++ standard Francis Glassborow <francis.glassborow@btinternet.com> - 2011-05-02 16:59 -0600

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