Order of evaluation

I wonder if construction like this (initialization list) has well defined EO (evaluation order):

struct MemoryManager
    {
        Pair* firstPair_;//<-beg
        Pair* currentPair_;
        Pair* lastPair_;//<-end

        MemoryManager():lastPair_(currentPair_ = firstPair_ = nullptr)
            {/*e.b.*/}
};

If yes I personally would prefer this way to the more conventional:

    MemoryManager():firstPair_(nullptr),
                    currentPair_(nullptr),
                    lastPair_(nullptr)
    {/*e.b*/}

Yes. As shown in your code, the members will be initialized in the same order they are declared in the struct/class definition (the order of initializers in the constructor definition is irrelevant, at best you will get a warning telling you they are in an incorrect order).

12.6.2 §5: Then, nonstatic data members shall be initialized in the order they were declared in the class definition (again regardless of the order of the mem-initializers).

However, the more conventional way has a reason to exist, namely that if the order of declaration of the variables changes (for instance, due to refactoring), the code will not break silently. People don't readily assume the order of declaration is relevant, unless a warning tells them otherwise.