If the people ask what is the different between pointer and reference,
what is the brief and good answer?
I say " pointer could point to NULL, but there is no null reference",
What is your opinion?
Vol
Aug 1 '06
14  7189 
"Victor Bazarov" <v.********@com Acast.netwrote in message
news:ea******** **@news.datemas .de...
Howard wrote:
>"Kaz Kylheku" <kk******@gmail .comwrote in message
news:11******* *************** @m73g2000cwd.go oglegroups.com. ..
>>Vols wrote:
If the people ask what is the different between pointer and
reference, what is the brief and good answer?
Brief and good answer:
In the context of C++, a reference is a declarative and type casting
gadget which causes an object itself to be propagated rather than a
copy of its value.
What??? What's a "declarativ e and type casting gadget", and what
does a reference have to do with type casting?
A reference is simply an "alias" for an existing object.
I think you need to remember that references help using objects
polymorphically .
True. I probably should have left out "simply" in my answer. A good C++
book is undoubtedly the best place for a complete description of references,
(not someone's "brief and good answer").
-Howard
Howard wrote:
True. I probably should have left out "simply" in my answer.
Or you should have simply left out your clueless answer.
"Kaz Kylheku" <kk******@gmail .comwrote in message
news:11******** **************@ h48g2000cwc.goo glegroups.com.. .
Howard wrote:
>True. I probably should have left out "simply" in my answer.
Or you should have simply left out your clueless answer.
Instead of a personal attack, you could let us know what you meant by your
own answer. Specifically, what do you mean by: "a declarative and type
casting gadget".
Also, it's not that clear what you meant when you said it "causes an object
itself to be propogated". A reference "refers" to another object. It's an
alias for that object. Propogation implies some sort of movement or
copying.
-Howard
Howard wrote:
"Kaz Kylheku" <kk******@gmail .comwrote in message
news:11******** **************@ m73g2000cwd.goo glegroups.com.. .
Vols wrote:
If the people ask what is the different between pointer and reference,
what is the brief and good answer?
Brief and good answer:
In the context of C++, a reference is a declarative and type casting
gadget which causes an object itself to be propagated rather than a
copy of its value.
What??? What's a "declarativ e and type casting gadget", and what does a
English lesson:
A gadget is a mechanism; a device. In a programming language, that is
syntax plus semantics. Declarative means having to do with
declarations, and type casting means having to do with type casts.
reference have to do with type casting?
Gee, I don't know! How about :
void func(Base &b)
{
Derived d = dynamic_cast<De rived &>(b);
}
That is a reference cast. Here, the reference isn't used to declare
anything. So if I had said that references were declarative gadget, I
would have missed the type casting use.
A reference is simply an "alias" for an existing object.
You're just parroting an oft repeated statement that only applies to
block scope reference variables. It is misleading to varying degrees if
applied to other situations. Entities which are not object-like can be
attributed as entities, such as function return values.
Also, when would an alias ever be constructed for a NON-existing
object?
"Kaz Kylheku" <kk******@gmail .comwrote in message
news:11******** **************@ m79g2000cwm.goo glegroups.com.. .
>
Howard wrote:
>"Kaz Kylheku" <kk******@gmail .comwrote in message
news:11******* *************** @m73g2000cwd.go oglegroups.com. ..
Vols wrote:
If the people ask what is the different between pointer and reference,
what is the brief and good answer?
Brief and good answer:
In the context of C++, a reference is a declarative and type casting
gadget which causes an object itself to be propagated rather than a
copy of its value.
What??? What's a "declarativ e and type casting gadget", and what does a
English lesson:
A gadget is a mechanism; a device. In a programming language, that is
syntax plus semantics. Declarative means having to do with
declarations, and type casting means having to do with type casts.
>reference have to do with type casting?
Gee, I don't know! How about:
void func(Base &b)
{
Derived d = dynamic_cast<De rived &>(b);
}
That is a reference cast. Here, the reference isn't used to declare
anything. So if I had said that references were declarative gadget, I
would have missed the type casting use.
The fact that you can cast something to a reference doesn't make the
reference a "type casting gadget". Your original statement was made to
someone who is a newbie, who didn't understand what a reference was. I
think your explanation was not very helpful in that context. That's why I
asked you to clarify it. I apologize if my reply sounded arrogant (esp. by
using the ???).
>A reference is simply an "alias" for an existing object.
You're just parroting an oft repeated statement that only applies to
block scope reference variables. It is misleading to varying degrees if
applied to other situations. Entities which are not object-like can be
attributed as entities, such as function return values.
Also, when would an alias ever be constructed for a NON-existing
object?
Oh, come on!
I don't mind discussing issues here, even if I'm shown to be wrong. But can
we keep this on a professional level?
-Howard This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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