|  | Destrying and object without calling a destructor | | |
| | | Bruno.DiStefano |  |
|  Posted: Wed Sep 03, 2008 8:58 am Post subject: Destrying and object without calling a destructor |  |
| |  | |
Hi All,
I have a large number of objects living in a double loop (see below,
where CYCLES and NUMBER are huge).
////////////////////////////////////////////////////////////////
for (t=0; t < CYCLES; t++)
{
for(i=0; i<NUMBER;i++)
{
MyClass[i].run(t);
}
}
////////////////////////////////////////////////////////////////
Along the way some objects should die and vanish from my execution. I
have no way of knowing which ones and I do not care. The output of my
program is an ascii file to be processed with other programs. I just
need to make sure that the objects which are supposed to die actually
die and that all memory associated to them is released, without
altering the order in which the other objects are stored. I do not
need a list. I am using and really need a vector. Given that I should
not call a destructor explicitely, what can I do?
Thank you.
Best regards
Bruno
--
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| |
| | | Thomas Richter | |
| | Posted: Wed Sep 03, 2008 7:21 pm Post subject: Re: Destrying and object without calling a destructor | |
| | | |
Bruno.DiStefano schrieb:
| Quote: | Hi All,
I have a large number of objects living in a double loop (see below,
where CYCLES and NUMBER are huge).
////////////////////////////////////////////////////////////////
for (t=0; t < CYCLES; t++)
{
for(i=0; i<NUMBER;i++)
{
MyClass[i].run(t);
}
}
////////////////////////////////////////////////////////////////
Along the way some objects should die and vanish from my execution. I
have no way of knowing which ones and I do not care. The output of my
program is an ascii file to be processed with other programs. I just
need to make sure that the objects which are supposed to die actually
die and that all memory associated to them is released, without
altering the order in which the other objects are stored. I do not
need a list. I am using and really need a vector. Given that I should
not call a destructor explicitely, what can I do?
|
Thrust the vector implementation to do that? I don't quite understand the question,
the vector *does* destroy all the objects it holds.
So long,
Thomas
--
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| |
| | | Erik Wikström | |
| | Posted: Wed Sep 03, 2008 8:53 pm Post subject: Re: Destrying and object without calling a destructor | |
| | | |
On 2008-09-03 10:58, Bruno.DiStefano wrote:
| Quote: | Hi All,
I have a large number of objects living in a double loop (see below,
where CYCLES and NUMBER are huge).
////////////////////////////////////////////////////////////////
for (t=0; t < CYCLES; t++)
{
for(i=0; i<NUMBER;i++)
{
MyClass[i].run(t);
}
}
////////////////////////////////////////////////////////////////
Along the way some objects should die and vanish from my execution. I
have no way of knowing which ones and I do not care. The output of my
program is an ascii file to be processed with other programs. I just
need to make sure that the objects which are supposed to die actually
die and that all memory associated to them is released, without
altering the order in which the other objects are stored. I do not
need a list. I am using and really need a vector. Given that I should
not call a destructor explicitely, what can I do?
|
If the objects are stored in the vector you can not free the memory they
occupy (without reordering) without destroying the vector. So you should
not store the objects in the vector, instead store (smart)pointers to
the actual objects , when an objects "dies" you can delete it and set
the pointer to 0.
Or you can redesign your objects using something like the PIMPL ideom so
you can free the majority of the memory used when an object is marked as
"dead".
--
Erik Wikström
[ See LINK for info about ]
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| |
| | | Mathias Gaunard | |
| | Posted: Wed Sep 03, 2008 8:58 pm Post subject: Re: Destrying and object without calling a destructor | |
On 3 sep, 10:58, "Bruno.DiStefano" <Bruno.DiStef...@gmail.com> wrote:
| Quote: | Along the way some objects should die and vanish from my execution. I
have no way of knowing which ones and I do not care.
|
That's not how it works. Object lifetime is to be well defined in
terms of ownership.
--
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| |
| | | Hyman Rosen | |
| | Posted: Wed Sep 03, 2008 9:44 pm Post subject: Re: Destrying and object without calling a destructor | |
Bruno.DiStefano wrote:
| Quote: | I do not need a list. I am using and really need a vector.
Given that I should not call a destructor explicitely, what
can I do?
|
It very much depends on the nature of your classes and
the time at which individual objects need to be destroyed.
The simplest thing you can do is to call
MyClass.erase(MyClass.begin() + i);
when you need to destroy element i. But this will slide
all the remaining elements up one slot.
--
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| |
|
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