The STL (C++) has priority_queue<T, Sequence, Compare>. But you can't just wrap it up for Perl, because the concepts behind the languages are too different.

Look at priority_queue: it is specialized for one type T, it uses a vector<T> by default for storage, but can use any other random-accessible Sequence type, and it uses the desired Compare "functor" for comparison (or T's < method by default). In return, it gives you type safety, with the usual C++ guarantees. The compiled code will typically inline the comparisons and the container's code, so it can be very fast.

There's no good translation of any of this into Perl. A useful Perl container will hold contents of all types. It will not be type safe, and the programmers using it will not expect it to be. Since access methods for containers are not standardized, it will be hard to make it work with another container. And containers and comparisons will probably need to be passed in a painfully slow way.

It's not that the idea has no merit, nor even that C++ RULEZ 4ND P3RL SUX. Just that STL comes from a very different world.

That said, wrapping one particular library-based implementation of a priority queue to work on standard Perl SVs would be very interesting, and quite possibly useful, too.