does the STL Class vector can hold any user define type?

#include <vector>

vector< MyCar> cars( 7 );

above OK?

"Jim Johnson" <aopiyy001@yahoo.com> wrote in message

> does the STL Class vector can hold any user define type?
>
> #include <vector>
>
> vector< MyCar> cars( 7 );

Yes. Did you try using it?

Sharad

On Apr 3, 8:34 pm, Jim Johnson <aopiyy...@yahoo.com> wrote:
> does the STL Class vector can hold any user define type?
>
> #include <vector>
>
> vector< MyCar> cars( 7 );
>
> above OK?

yes, ensure the user defined type is copy constructable and
assignable.

Thanks,
Balaji.

Jim Johnson wrote:

> does the STL Class vector can hold any user define type?

No. As all containers, the value types need to satisfy the
copy-constructible and assignable conceptual requirements. Using a vector
on a type that does not is undefined behavior.

Also: some functions may require default constructability.


> #include <vector>
>
> vector< MyCar> cars( 7 );
>
> above OK?

Depends on MyCar. The above will require MyCar to be copy-constructible,
assignable, and default-constructible.


Guessing from the name "MyCar", the class could be a class for which
copy-construction and assignment doesn't make sense (since cars are
entities and don't get copied and assigned in the real-world domain where
one deals with them). In that case, you might consider vector< MyCar* > or
some smart-pointer variant thereof. (This also takes care of the possible
need for polymorphic cars in the vector.)


Best

Kai-Uwe Bux

On 2008-04-03 21:34:54 -0400, Jim Johnson <aopiyy001@yahoo.com> said:

> does the STL Class vector can hold any user define type?
>

vector is not a class. It is a template. If you don't make that
distinction you'll end up thoroughly confused.

--
Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)

kasthurirangan.balaji@gmail.com wrote:
> On Apr 3, 8:34 pm, Jim Johnson <aopiyy...@yahoo.com> wrote:
>> does the STL Class vector can hold any user define type?
>>
>> #include <vector>
>>
>> vector< MyCar> cars( 7 );
>>
>> above OK?
>
> yes, ensure the user defined type is copy constructable and
> assignable.
>
PLUS the type can not be a local or unnamed type or derived
therefrom.

Ron Natalie wrote:

> kasthurirangan.balaji@gmail.com wrote:
>> On Apr 3, 8:34 pm, Jim Johnson <aopiyy...@yahoo.com> wrote:
>>> does the STL Class vector can hold any user define type?
>>>
>>> #include <vector>
>>>
>>> vector< MyCar> cars( 7 );
>>>
>>> above OK?
>>
>> yes, ensure the user defined type is copy constructable and
>> assignable.
>>
> PLUS the type can not be a local or unnamed type or derived
> therefrom.

That's generally true for any type used as template argument. BTW:
Can you have a type that is derived from a local or unnamed type, but isn't
itself one?

Rolf Magnus wrote:

> That's generally true for any type used as template argument. BTW:
> Can you have a type that is derived from a local or unnamed type, but isn't
> itself one?
>
Yep, but I wanted to head off the next question when he tries do do
something like:
int foo() {
struct x { int a; };
vector<x> v;
}

Derived, may be not, but the standard uses compounded from
rather than derived...and that you can do.