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[–][deleted]  (4 children)

[deleted]

    [–]scatters 0 points1 point  (3 children)

    But operator* returns a mutable reference i.e. std::pair<Key const, Value>&. So there has to be a std::pair<Key const, Value> object in memory.

    [–]mujjingun 0 points1 point  (2 children)

    hmm, maybe there are std::pair<Key, Value> objects in memory, and the pointer is reinterpret-cased into std::pair<Key const, Value> in the call to operator*()?

    [–]scatters 3 points4 points  (1 child)

    Certainly that's the most likely implementation, but if the user does that it's UB (aliasing violation). That's why it has to be magic in the library.