Why doesn't std::vector::push_front() exist? : <p>Since <code>std::vector::push_back()</code> exists, why doesn't <code>std::vector::push_front()</code> exist too? </p>

<p>I know there are others storage objects that work pretty much the same way and have an implementation of both <code>push_back()</code> and <code>push_front()</code> functions, but I was curious about the reason why <code>std::vector</code> doesn't.</p>
