Re: Is this valid and moral C++?
"Filimon Roukoutakis" <filimon@phys.uoa.gr> wrote in message
news:etk69j$c56$1@cernne03.cern.ch...
: Suppose that we have a function
:
: f(Object*& obj)
:
: and have declared a global std::vector<Object*> vec;
:
: Is it valid to do
:
: void g() {
: vec.push_back(new Object);
: f(vec.back());
: }
:
: ie does f() internally actually have read/write access to the Object
: allocated in g() on the heap? If not, what would be the trick to
achieve
: this? Thanks,
That part is ok. The only problem I see in the above code is
something that hasn't been mentioned yet:
vec.push_back(new Object);
This is not exception-safe: if push_back fails (because it
is unable to allocate a larger block of memory), the newly
allocated object will be leaked.
But this of course will be unrelated to the problem
you described later.
For that, be careful that you do not modify the vector
(e.g. by adding another element) as long as you are
using the reference returned by back().
hth -Ivan
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