I know it's generally bad from to derive from STL containers. That
said, here's my question:
I am using std::priority_q ueue<>. However, I need to be able to access
the underlying container; specifically, I need to be able to get at
begin() and end() for it.
Josuttis (10.3.3) shows that the compare operator and the container are
*protected* members of std::priority_q ueue. This would lead me to
believe that it was intended for derivation. I was thinking about doing
something like this:
class my_data { /* contents redacted */ };
class my_priority_que ue : private std::priority_q ueue<my_data>
{
public:
typedef std::priority_q ueue<my_data> pq;
using pq::top;
using pq::push;
using pq::pop;
using pq::empty;
using pq::size;
my_priority_que ue();
~my_priority_qu eue();
void do_something_to _all_elements() ; // uses c.begin() and c.end()
};
Is this kosher? 2 1547
red floyd wrote: I know it's generally bad from to derive from STL containers.
It's fine to derive from STL containers.
That said, here's my question:
I am using std::priority_q ueue<>. However, I need to be able to access the underlying container; specifically, I need to be able to get at begin() and end() for it.
Josuttis (10.3.3) shows that the compare operator and the container are *protected* members of std::priority_q ueue. This would lead me to believe that it was intended for derivation. I was thinking about doing something like this:
class my_data { /* contents redacted */ }; class my_priority_que ue : private std::priority_q ueue<my_data> { public: typedef std::priority_q ueue<my_data> pq; using pq::top; using pq::push; using pq::pop; using pq::empty; using pq::size; my_priority_que ue(); ~my_priority_qu eue(); void do_something_to _all_elements() ; // uses c.begin() and c.end() };
Is this kosher?
In theory, this should work, however a (in)famous C++ compiler does not
accept this. (MSVC). To work around it, I redefine the methods inline
in the dervied class.
Gianni Mariani wrote: red floyd wrote:
I know it's generally bad from to derive from STL containers.
It's fine to derive from STL containers.
That
said, here's my question:
I am using std::priority_q ueue<>. However, I need to be able to access the underlying container; specifically, I need to be able to get at begin() and end() for it.
Josuttis (10.3.3) shows that the compare operator and the container are *protected* members of std::priority_q ueue. This would lead me to believe that it was intended for derivation. I was thinking about doing something like this:
class my_data { /* contents redacted */ }; class my_priority_que ue : private std::priority_q ueue<my_data> { public: typedef std::priority_q ueue<my_data> pq; using pq::top; using pq::push; using pq::pop; using pq::empty; using pq::size; my_priority_que ue(); ~my_priority_qu eue(); void do_something_to _all_elements() ; // uses c.begin() and c.end() };
Is this kosher?
In theory, this should work, however a (in)famous C++ compiler does not accept this. (MSVC). To work around it, I redefine the methods inline in the dervied class.
Thanks. I guess that it's MSVC6 that doesn't like it. MSVC7.1 does,
as does g++ 3.2.2 This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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last post by:
Hopefully a simple question:
What is the best/safest/fastest way to clear/make empty a std::priority_queue?
Thanks,
Ryan
|
by: Dave |
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Hello all,
I'm pondering why the default underlying container for std::priority_queue<>
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In using std::priority_queue, I'm concerned about the expense of
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std::vector has reserve() to address this concern, though there
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Regards,
Ryan
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