What is the difference between copy initialization and assignment.
How the memory will allocates the objects.
Thanks ®ards,
Sai Kishore
7  3733  sk*******@yahoo .co.in wrote: What is the difference between copy initialization and assignment.
Assignment changes the value of an existing object. Initialisation
creates a new object. They are fundamentally different things.
Copy-initialisation is one type of initialisation which creates a new
object as a copy of an existing object. Where are you learning C++? In
a class? From a book? Has this not been explained?
How the memory will allocates the objects.
If you understand the answer to the first question, the answer to this
question should be clear. But it might not be, so ask for clarification
of anything you still don't understand.
Gavin Deane
<sk*******@yaho o.co.in> wrote in message
news:11******** **************@ i39g2000cwa.goo glegroups.com.. .
| What is the difference between copy initialization and assignment.
|
| How the memory will allocates the objects.
|
| Thanks ®ards,
| Sai Kishore
|
Assignment implies a brand new object or a target for modification: an
l-value.
A copy is a clone constructor. Sometimes not an identical clone.
Peter_Julian wrote: <sk*******@yaho o.co.in> wrote in message
news:11******** **************@ i39g2000cwa.goo glegroups.com.. .
| What is the difference between copy initialization and assignment.
|
| How the memory will allocates the objects.
|
| Thanks ®ards,
| Sai Kishore
|
Assignment implies a brand new object or a target for modification: an
l-value.
Assignment is when the value of an existing object is overwritten with
a new value. How does that imply a brand new object?
Gavin Deane
Hi Gavin,
I am asking that , Is it same memory allocation is used
for assignment operatot?
In copy initialization Is it different memory allcation.
Suppose if you take two objects , these two objects will use same
memory allcation or different memory allocation in assignment and copy
initialization.
"Gavin Deane" <de*********@ho tmail.com> wrote in message
news:11******** **************@ i39g2000cwa.goo glegroups.com.. .
|
| Peter_Julian wrote:
| > <sk*******@yaho o.co.in> wrote in message
| > news:11******** **************@ i39g2000cwa.goo glegroups.com.. .
| > | What is the difference between copy initialization and assignment.
| > |
| > | How the memory will allocates the objects.
| > |
| > | Thanks ®ards,
| > | Sai Kishore
| > |
| >
| > Assignment implies a brand new object or a target for modification: an
| > l-value.
|
| Assignment is when the value of an existing object is overwritten with
| a new value. How does that imply a brand new object?
|
| Gavin Deane
|
read again, i didn't need to overload operator| here.
Peter_Julian wrote: "Gavin Deane" <de*********@ho tmail.com> wrote in message
news:11******** **************@ i39g2000cwa.goo glegroups.com.. .
|
| Peter_Julian wrote:
| > Assignment implies a brand new object or a target for modification: an
| > l-value.
|
| Assignment is when the value of an existing object is overwritten with
| a new value. How does that imply a brand new object?
|
| Gavin Deane
|
read again, i didn't need to overload operator| here.
Nope. I don't get it. Sorry. Can you clarify where a brand new object
might participate in assignment? A brand new object can't be the target
of assignment.
Gavin Deane
Please quote some relevant context from the message you are replying
to. From Google Groups, don't use the "Reply" link at the bottom of the
message. Click on "Show Options" at the top of the message and use the
"Reply" link that reveals. sk*******@yahoo .co.in wrote: Hi Gavin,
I am asking that , Is it same memory allocation is used
for assignment operatot?
As I said before, assignment changes the value of an existing object.
There is not necessarily any memory allocation at all.
There will be memory allocation *if* you are assigning to an object of
a type with a user-defined assignment operator *and* that assignment
operator allocates some memory. Are you considering assignment of such
a type? Or are you considering assignment as a concept in general?
In copy initialization Is it different memory allcation.
With any form of initialisation, including but not limited to
copy-initialisation, a new object is being created, so at the very
least some memory will be allocated for that object. In addition, for
copy-initialisation, there will be further memory allocation *if* you
are creating an object of a type with a user-defined copy constructor
*and* that copy constructor allocates some memory.
Suppose if you take two objects , these two objects will use same
memory allcation or different memory allocation in assignment and copy
initialization.
I don't understand that. It might help if you showed some code as an
example of the situation you are asking about. If you do that, make
sure you follow the guidelines in the FAQ for posting code otherwise it
won't help at all. http://www.parashift.com/c++-faq-lit...t.html#faq-5.8
Gavin Deane This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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