[top-level]
rules:
[after 10, unstable]	~a -> c+
[after 10, unstable]	b -> c-
	0	a : 1
	0	b : 0
	0	a : 0
queue:	10	c : 1	[from a:=0]
	0	a : 1
event c+ was silently killed 
	0	b : 1
queue:	10	c : 0	[from b:=1]
	0	b : 0
event c- was silently killed 
	0	b : 1
	10	c : 0	[by b:=1]
	10	b : 0
	10	a : 0
queue:	20	c : 1	[from a:=0]
	10	a : 1
event c+ was silently killed 
testing weak instability... 
	10	a : 0
queue:	20	c : 1	[from a:=0]
	10	a : X
	20	c : X	[by a:=X]
should suppress c+ weak unstable 
c should still become X 
	20	a : 0
	30	c : 1	[by a:=0]
	30	a : 1
	30	b : 1
queue:	40	c : 0	[from b:=1]
	30	b : X
	40	c : X	[by b:=X]
should suppress c- weak unstable 
c should still become X 
