[_ph_]

This is an interesting point. On the first glance, it looks like a very obvious missing piece and having to hand-write such expressions feels like unnecessary painful.

On the second glance, one can see why probably it was left out: there are two fundamental different ways to implement the deletion. You can copy the last element into the slot of the deleted element, or you can move all elements after the deleted one place to the left. The latter is what you implemented and preserves the ordering, which often is desirable. The former is way more efficient, if you don't need to preserve the order. A default implementation would probably choose to preserve the order and thus introduce a systematic inefficiency which is easy to be avoided.

Fortunately, with the introduction of generics and especially the new slice package, this discussion becomes moot.