Method emplace

src/module.cpp:77–84

    template <class... Ts>
    instruction_ref emplace(instruction_ref pos, Ts&&... xs)
    {
        changed.notify();
        // cppcheck-suppress redundantInitialization
        auto r = instructions.emplace(pos, std::forward<Ts>(xs)...);
        instruction_set.insert(std::addressof(*r));
        return r;
    }
    instruction_ref insert(instruction_ref pos, const instruction& ins)
    {
        changed.notify();