Survey: what new bit of syntax would you like in base #RStats?

What should the following bits of syntax do?

* ===
* ++ And --
* +=
* //
* ?
* {{ }}
* [[[ ]]]
* <<==
* (?: X)

#RStats syntax hypothetical

count += 2

Increases 'count' by 2

Which means the following would be valid:

p <- ggplot()
p += geom_point(...)
p += geom_text(...)

@coolbutuseless What about count +<- 2