Newbie question on vectors of pointers

[kelvSYC]

My mind seems to be having a brain freeze. Anyways, here goes:

I have a function that constructs an A from some other data, like so:

A foo();

and I would like to add something returned from it into a
std::vector<A*> elsewhere in my code. To do so, do I just do so, like

std::vector<A*> list;
list.push_back(&foo());

Or do I have to change foo() so that it returns a pointer? If so, (and
here's where my knowledge of C++ is shaky), can I only return something
that's allocated using new? If so, will that item be automatically
deleted once the vector is deallocated (or would I have to write
something extra?

 

[Axter]

My mind seems to be having a brain freeze. Anyways, here goes:

I have a function that constructs an A from some other data, like so:

A foo();

and I would like to add something returned from it into a
std::vector<A*> elsewhere in my code. To do so, do I just do so, like

std::vector<A*> list;
list.push_back(&foo());

Or do I have to change foo() so that it returns a pointer? If so, (and
here's where my knowledge of C++ is shaky), can I only return something
that's allocated using new? If so, will that item be automatically
deleted once the vector is deallocated (or would I have to write
something extra?

foo() should be returning something that will exist outside the scope
of foo().
More then likely it would need to be something created via new
operator.
And you would then have to delete this before clearing your vector.

You haven't stated why you're using a vector of pointers.
You probably don't need it to be pointers, and instead you should have
a vector of concrete type.
std::vector<A> Myvect;
Then you can leave foo as is.
Myvect.push_back(foo());
I also recommend not naming your objects by the same name as other
objects in the STL, like list.