My understanding of the containers in the Standard Library is that they can
move out from under pointers and references if they are resized.
Stroustrup suggests I can reserve the capacity I will need, and thus avoid
having the vector (or other container) realocated with a different address
range. I have the sense this is not explicitly specified in the Standard.
I have not, however, read the entire ISO/IEC 14882:2003. Here's a link to
an oder version draft of the Standard: http://www.kuzbass.ru:8086/docs/isoc...tml#lib.vector
// lib.vector.capa city capacity:
size_type size() const;
size_type max_size() const;
void resize(size_typ e sz, T c = T());
size_type capacity() const;
bool empty() const;
void reserve(size_ty pe n);
Is it reasonable for me to assume my vector /will/ stay put if I don't force
a reallocation by adding to it?
--
STH
Hatton's Law: "There is only One inviolable Law"
KDevelop: http://www.kdevelop.org SuSE: http://www.suse.com
Mozilla: http://www.mozilla.org 3  1344 
Steven T. Hatton wrote: ...
Is it reasonable for me to assume my vector /will/ stay put if I don't force
a reallocation by adding to it?
Yes. It is specified in the standard.
--
Best regards,
Andrey Tarasevich
On Thu, 06 May 2004 20:58:29 -0400, "Steven T. Hatton"
<su******@setid ava.kushan.aa> wrote: My understanding of the containers in the Standard Library is that they can
move out from under pointers and references if they are resized.
Stroustrup suggests I can reserve the capacity I will need, and thus avoid
having the vector (or other container) realocated with a different address
range. I have the sense this is not explicitly specified in the Standard.
I have not, however, read the entire ISO/IEC 14882:2003. Here's a link to
an oder version draft of the Standard:
http://www.kuzbass.ru:8086/docs/isoc...tml#lib.vector
// lib.vector.capa city capacity:
size_type size() const;
size_type max_size() const;
void resize(size_typ e sz, T c = T());
size_type capacity() const;
bool empty() const;
void reserve(size_ty pe n);
Is it reasonable for me to assume my vector /will/ stay put if I don't force
a reallocation by adding to it?
The word you're interested here is "invalidate s". You wish to avoid
anything that invalidates references, pointers and iterators into the
vector. If you search the Standard for "invalidate s", you'll find
23.2.4.2/5, which answers your direct question, and also a bit later the
section on vector::erase() explains what gets invalidated when you use
that.
-leor
--
Leor Zolman --- BD Software --- www.bdsoft.com
On-Site Training in C/C++, Java, Perl and Unix
C++ users: download BD Software's free STL Error Message Decryptor at: www.bdsoft.com/tools/stlfilt.html
"Steven T. Hatton" <su******@setid ava.kushan.aa> wrote in message
news:9c******** ************@sp eakeasy.net...
My understanding of the containers in the Standard Library is that they
can move out from under pointers and references if they are resized.
Stroustrup suggests I can reserve the capacity I will need, and thus avoid
having the vector (or other container) realocated with a different address
range. I have the sense this is not explicitly specified in the Standard.
I have not, however, read the entire ISO/IEC 14882:2003. Here's a link to
an oder version draft of the Standard:
http://www.kuzbass.ru:8086/docs/isoc...tml#lib.vector
// lib.vector.capa city capacity:
size_type size() const;
size_type max_size() const;
void resize(size_typ e sz, T c = T());
size_type capacity() const;
bool empty() const;
void reserve(size_ty pe n);
Is it reasonable for me to assume my vector /will/ stay put if I don't
force a reallocation by adding to it?
Yes. However you can get the begin or end (one past the end element) of the
vector whenever you want, so you can do for example:
#include <vector>
int main()
{
using std::vector;
vector<int>a(10 );
vector<int>::it erator p=a.begin()+3;
*p=7;
a.push_back(4);
// p continues to point at a[3]
p=a.begin()+3;
}
Regards,
Ioannis Vranos This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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