Hi,
I have doubts reg virtual constructor
what is virtual constructor?
Is c++ supports virtual constructor?
Can anybody explain me about virtual constructor?
Regards,
Mani
16  3758 
plmanikandan wrote: Can anybody explain me about virtual constructor?
Raw C++ cannot call a constructor virtually (because a constructor is not
really a function). There's probably some common design pattern.
How about you use Google to survey the topic and report back here?
--
Phlip http://www.greencheese.org/ZeekLand <-- NOT a blog!!!
hii,
there is no such thing as virtual constructor in c++, it doesn't make
sense.
a constructor IS a function(can be defined explicitly , compiler calls
it when an object of a
class is CREATED.)
A virtual destructor is required to resolve the ambiguity,when a
derived class object
is deleted via a base class pointer(a 'derived class' IS A 'base
class') since compiler
has to decide what to delete derived object or base object.
thus declareing the destructor virtual resolves the ambugity.
concept of virtual constructor doesnt' make sense to me.
please correct me if nething is out of place here.
thanks
* pl**********@gm ail.com:
I have doubts reg virtual constructor
Note: "doubt" means you are unsure whether something is true or not, or
whether a person is truthful or reliable, or not.
Your usage above is meaningless and probably due to a bad dictionary.
what is virtual constructor?
See the FAQ. Use the FAQ's Google search (it's on the main page of the
FAQ) to find the phrase "virtual constructor" in the FAQ. Apart from
that meaning, which has only a peripheral connection to the words
"virtual" and "constructo r" (it's more like a random phrase that for
some historical reason has acquired a given meaning), the FAQ also
discusses another more natural meaning; search the FAQ for the phrase
"Dynamic Binding During Initialization" to find that discussion.
Is c++ supports virtual constructor?
Yes.
Can anybody explain me about virtual constructor?
Yes, see the FAQ.
Hth.,
- Alf
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail? pl**********@gm ail.com wrote: Hi,
I have doubts reg virtual constructor
what is virtual constructor?
Is c++ supports virtual constructor?
Can anybody explain me about virtual constructor?
Regards,
Mani
When you make a function virtual that function is binded after the
object has been created.
But if you take a constructor it is called at the time of creation of
the object.
Constructor cannot be binded after the object is created.
dude how can the constructors can be virtual ??
here is the reference frm bjarne stroustrup's tech. faq: http://public.research.att.com/~bs/b...l#virtual-ctor
Alf P. Steinbach wrote: * pl**********@gm ail.com:
I have doubts reg virtual constructor
Note: "doubt" means you are unsure whether something is true or not, or
whether a person is truthful or reliable, or not.
Your usage above is meaningless and probably due to a bad dictionary.
what is virtual constructor?
See the FAQ. Use the FAQ's Google search (it's on the main page of the
FAQ) to find the phrase "virtual constructor" in the FAQ. Apart from
that meaning, which has only a peripheral connection to the words
"virtual" and "constructo r" (it's more like a random phrase that for
some historical reason has acquired a given meaning), the FAQ also
discusses another more natural meaning; search the FAQ for the phrase
"Dynamic Binding During Initialization" to find that discussion.
Is c++ supports virtual constructor?
Yes.
Can anybody explain me about virtual constructor?
Yes, see the FAQ.
Hth.,
- Alf
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
* al pacino: [top-posting]
[quoting extranous material]
[quoting signature]
Please don't top-post. Please don't quote irrelevant stuff. See the
FAQ and Shiva's monthly "Welcome"-posting in this group.
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
"Alf P. Steinbach" <al***@start.no > wrote in message
news:47******** ****@individual .net... * pl**********@gm ail.com:
I have doubts reg virtual constructor
Note: "doubt" means you are unsure whether something is true or not, or
whether a person is truthful or reliable, or not.
Your usage above is meaningless and probably due to a bad dictionary.
Actually, it's probably because he's Norweigian and English is not his
primary language. what is virtual constructor?
See the FAQ. Use the FAQ's Google search (it's on the main page of the
FAQ) to find the phrase "virtual constructor" in the FAQ. Apart from that
meaning, which has only a peripheral connection to the words "virtual" and
"constructo r" (it's more like a random phrase that for some historical
reason has acquired a given meaning), the FAQ also discusses another more
natural meaning; search the FAQ for the phrase "Dynamic Binding During
Initialization" to find that discussion.
Is c++ supports virtual constructor?
Yes.
No. From the FAQ 20.8 in part:
An idiom that allows you to do something that C++ doesn't directly support. Can anybody explain me about virtual constructor?
Yes, see the FAQ.
Yes, see the FAQ 20.8 You can't have a virtual constructor, but you can
have something that mimics what a virtual constructor would do.
Again, FAQ 20.8 in a bigger part:
You can get the effect of a virtual constructor by a virtual clone() member
function (for copy constructing), or a virtual create() member function (for
the default constructor).
Here is the link to the FAQ 20.8: http://www.parashift.com/c++-faq-lit....html#faq-20.8
al pacino wrote: dude how can the constructors can be virtual ??
Easy. What is commonly called a "virtual constructor" just happens not to be
a constructor (like the Holy Roman Empire was neither roman nor holy and it
is debatable whether it was an empire).
here is the reference frm bjarne stroustrup's tech. faq:
http://public.research.att.com/~bs/b...l#virtual-ctor
Did you read what he wrote there? I quote from *that* page:
Techniques for using an indirection when you ask to create an object
are often referred to as "Virtual constructors". For example, see
TC++PL3 15.6.2.
Alf P. Steinbach wrote: * pl**********@gm ail.com:
[snip]
And please, don't top-post.
Best
Kai-Uwe Bux
* Jim Langston: "Alf P. Steinbach" <al***@start.no > wrote in message
news:47******** ****@individual .net... * pl**********@gm ail.com: I have doubts reg virtual constructor
Note: "doubt" means you are unsure whether something is true or not, or
whether a person is truthful or reliable, or not.
Your usage above is meaningless and probably due to a bad dictionary.
Actually, it's probably because he's Norweigian and English is not his
primary language.
what is virtual constructor?
See the FAQ. Use the FAQ's Google search (it's on the main page of the
FAQ) to find the phrase "virtual constructor" in the FAQ. Apart from that
meaning, which has only a peripheral connection to the words "virtual" and
"constructo r" (it's more like a random phrase that for some historical
reason has acquired a given meaning), the FAQ also discusses another more
natural meaning; search the FAQ for the phrase "Dynamic Binding During
Initialization" to find that discussion.
Is c++ supports virtual constructor?
Yes.
No. From the FAQ 20.8 in part:
An idiom that allows you to do something that C++ doesn't directly support.
Can anybody explain me about virtual constructor?
Yes, see the FAQ.
Yes, see the FAQ 20.8 You can't have a virtual constructor, but you can
have something that mimics what a virtual constructor would do.
Again, FAQ 20.8 in a bigger part:
You can get the effect of a virtual constructor by a virtual clone() member
function (for copy constructing), or a virtual create() member function (for
the default constructor).
Here is the link to the FAQ 20.8:
http://www.parashift.com/c++-faq-lit....html#faq-20.8
I'm not sure what point (if any) you were trying to make? Confuse the
newbie, and remove his or her learning experience in searching the FAQ?
Look how smart I am, I managed to find it in the FAQ?
Anyway, your unqualified "no" above is incorrect. C++ does indeed
support all that's needed to implement what's known as a virtual
constructor, including virtual member functions and function result
covariance. Note that this does not contradict the FAQ's statement.
Hth.,
- Alf
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail? This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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