Changing note or rest length and automatically shifting the following notes and rests

It would be nice to have a feature whereby you could select a note or rest within a bar and change its length or delete it and have all the following notes shifted up or down the bar as appropriate.
So,
If the request increases the value of the rest or note then the following notes are shifted up the bar and the final rest or note in the bar is shortened accordingly.
If the request decreases (or deletes) the length of the selected note or rest then the following notes are shifted down accordingly and the final note or rest of the bar is lengthened.

At the moment the only way I know to do this is by copying and pasting to perform the shifting action - a bit cumbersome.