This is a slightly more complicated analog of the [Queue], where enqueues (insertions) also respect a priority. This is currently implemented through three separate singly-linked lists, but there's considerably better (just tricky) ways of implementing it. None of these would change the interface.
No indexors, iterators, or queries are implemented for this type, as maintaining proper semantics forbids it.
Z 3f99cddd7b06658dec33d1d02ea0f05d