class A
def A.set a
@@a = a
end
def A.get
@@a
end
end
class B
def B.set a
@@a = a
end
def B.get
@@a
end
end
B.set 1
p B.get
A.set 2
p A.get
p B.get
class A
@@a = 1 # executed when class is read
def self.set x
@@a = 2 # executed when A.set is executed
end
end
B——-A
@@a
B——-A
@@a @@a