Template question in C++

[grscot]

Dear all, I need to use an array of Book pointers (BookList) and Member (MemberList). Both of them are compound (container) classes. The component objects are books and members (up to 10)for each list respectively. Is the below implementation of the array.h file correct? #ifndef _ARRAY #define _ARRAY const int MAX_VALUE=10; template class Array { public: Array(int maximum=10); ~Array(); ...... private: Object* array_list[MAX_VALUE]; //To keep track of the elements into the list. int num_of_elements; }; #endif Regards, grscot

[Alvaro Mendez]

It looks OK, but does it compile? :-) If it compiles, the rest is a matter of making sure it has no bugs, which the debugger will help you determine. Now, as far as what I would do if I were you, I'd try to use a container class from one of the available libraries, be it MFC or STL. STL is more sophisticated and portable, but also more difficult for beginners. MFC is simpler and better documented. So take your pick: MFC: typedef **CTypedPtrArray**<CPtrArray, Book> BookList; STL: typedef **vector**< auto_ptr<Book> > BookList; Regards, Alvaro

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When birds fly in the right formation, they need only exert half the effort. Even in nature, teamwork results in collective laziness. -- despair.com

[Anonymous]

Thanks a lot Alvaro Mendez Regards, grscot

[Joaquin M Lopez Munoz]

std::vectors of auto_ptrs are a no-no. There are tons of articles explaining why this is not safe --briefly put, STL assumes objects inside a container have standard copy semantics, which auto_ptrs do not have. Instead, one can use boost::shared_ptr (see www.boost.org[^]). Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

[Alvaro Mendez]

Wow, I had no idea. Could you point me to one of those articles you mention? I mean, I'd like to see under what circumstances a vector of auto_ptrs does not work as expected, so that I can steer clear of such scenarios. The auto_ptr class has a simple and straightforward copy constructor/assignment operator; it's hard to imagine that it wouldn't work as expected under typical usage. Thanks, Alvaro

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When birds fly in the right formation, they need only exert half the effort. Even in nature, teamwork results in collective laziness. -- despair.com

[Joaquin M Lopez Munoz]

See for instance, Danny Kalev's The Top 20 C++ Tips of All Time[^], tip 20. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo