r -> o

!r&o->v

parses as:
left !r&o
method -
right v


valid statements:

t -> o
f -> r
r|w |> b
t&w -> g
(r|w)&>3 => o
r|w&%2 => g
g&%3+1 *> v
(%3+1&( r | w )) &> 2 |> y
