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getting a type ID during new operator overloading


Hi, guys,

I need to overload global "new" operator but I have to know the type id
"new" is begin invoked on.
For example if I overload it like this

void *operator new(size_t n)
{
...body...
}

I can only use "n" to get the size of object of whatever type is being
instantiated.
Is it possible to know the type?

thanks in advance

Jul 23 '05 #1
5 1923
<bi********@gma il.com> wrote...
I need to overload global "new" operator but I have to know the type id
"new" is begin invoked on.
Why? Isn't that what class-specific operator new is for?
For example if I overload it like this

void *operator new(size_t n)
{
...body...
}

I can only use "n" to get the size of object of whatever type is being
instantiated.
Is it possible to know the type?


No. Unless, of course, you somehow ensure that all your classes have
different sizes...

V
Jul 23 '05 #2
>Why? Isn't that what class-specific operator new is for?
Class specific operator is no use here. Part of my program uses memory
manager allocating memory by my_new(Type)(.. .constructor params...) for
example
my_new(int), my_new(MyClass) (123,"123")

But part is just using new. It is too big to go and start changing it
by hand, so I wanted to overload global new.

void *operator new(size_t n)
{
my_new( <type should goes here> )
}

Problem is - I need type.

Jul 23 '05 #3
bi********@gmai l.com wrote:
Why? Isn't that what class-specific operator new is for?
Class specific operator is no use here. Part of my program uses memory
manager allocating memory by my_new(Type)(.. .constructor params...) for
example
my_new(int), my_new(MyClass) (123,"123")


Is this a macro of some kind? Are you implementing memory debugging that
way? There are tools for that, you know...
But part is just using new. It is too big to go and start changing it
by hand,
That's what search-and-replace functionality in modern text editors is
for, isn't it?
so I wanted to overload global new.

void *operator new(size_t n)
{
my_new( <type should goes here> )
}

Problem is - I need type.


Sorry, no such thing available. I believe you're going to be better off
doing the "changing by hand" thing. You need to only do it once, and when
done, you can continue using your macro.

V
Jul 23 '05 #4
Is this a macro of some kind? Are you implementing memory debugging thatway? There are tools for that, you know...
That's what search-and-replace functionality in modern text editors is for, isn't it?


Whatever I am implementing, that was just an example.
Don't try to be a smart ass and spare me your sarcasm. I asked a simple
question. No need to tell me about text editors functionality. Thank
you.

Jul 23 '05 #5
<bi********@gma il.com> wrote...
[...] Thank you.


You're most welcome.
Jul 23 '05 #6

This thread has been closed and replies have been disabled. Please start a new discussion.

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