C++ boost - Is there a container working like a queue with direct key access?
boost, c++, containers, stl
Solution
Boost multi-index provides this kind of container.
To implement it myself, I'd probably go for a `map` whose values consist of a linked list node plus a payload. The list node could be hand-rolled, or could be Boost intrusive.
Note that the main point of the `queue` adaptor is to hide most of the interface of Sequence, but you want to mess with the details it hides. So I think you should aim to reproduce the interface of `queue` (slightly modified with your altered semantics for `push`) rather than actually use it.
Problem
I was wonndering about a queue-like container but which has key-access, like a map. My goal is simple : I want a FIFO queue, but, if I insert an element and an element with a given key is already in the queue, I want it the new element to replaced the one already in the queue. For example, a map ordered by insertion time would work . If there is no container like that, do you think it can be implemented by using both a queue and a map ?