But Set can just overwrites the specified element while Insert will insert the element at the specified position by pushing the element and all following elements out of the way.
> But Set can just overwrites the specified element
Kind of: Set returns a new Vector with a changed state (the specified element overwritten).
But yes, this implement is very sparse: there's no way to add and remove elements in the middle, no way to even tell how many elements are in the list: https://news.ycombinator.com/item?id=8592178
Perhaps omitting them hides some different optimisation choices (i.e. they would be more expensive)
