Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp[i])?
If the vector increases in size could it invalidate that pointer?
"Eric" <em*****@myrealbox.com> wrote in message
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Say I have vector<int> tmp. I then call a function that needs a pointer to an int in tmp. Is it wise to pass the function &(tmp[i])? If the vector increases in size could it invalidate that pointer?
not if you stick to adding elements, if you plan on erasing some, you
shouldn't use it, switching to list might help.
Say I have vector<int> tmp. I then call a function that needs a pointer to an int in tmp. Is it wise to pass the function &(tmp[i])?
Yes. AFAIK, it is blessed by the standard.
If the vector increases in size could it invalidate that pointer?
Yes. The vector might be reallocated to accommodate for new elements.
This will invalidate all iterators and pointers derived from iterators.
Best
"Flzw" <fl****@wanadoo.fr> wrote in message
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"Eric" <em*****@myrealbox.com> wrote in message news:a6*************************@posting.google.co m...
Say I have vector<int> tmp. I then call a function that needs a pointer to an int in tmp. Is it wise to pass the function &(tmp[i])? If the vector increases in size could it invalidate that pointer? not if you stick to adding elements, if you plan on erasing some, you
Wrong! std::vector::push_back CAN cause invalidation, and most certainly
will if the capacity of the vector is insufficient.
when using vectors with pointers of objects. is it best to create instances
then point to them or dynamic allocation upon creating a vector element.
I can do this, but is creating a vector with...
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