[top-level]
rules:
[after 10, unstable]	~a -> c+
[after 10]	b -> c-
	0	a : 1
	0	b : 0
	0	a : 0
queue:	10	c : 1	[from a:=0]
	0	a : 1
No event pending on `c'.
event c+ was turned into vacuous X 
	0	b : 1
queue:	10	c : 0	[from b:=1]
WARNING: unstable `c'-
rule: [after 10]	b:0 -> c-:X
>> cause: `b' (val: 0)
	0	b : 0
should report c- unstable 
queue:	10	c : X	[from b:=1]
event c- was turned into vacuous X 
	10	c : X	[by b:=0]
	10	b : 1
	20	c : 0	[by b:=1]
	20	b : 0
	20	a : 0
queue:	30	c : 1	[from a:=0]
	20	a : 1
No event pending on `c'.
event c+ was killed 
resetting c:0 
	20	b : 1
	20	b : 0
testing weak instability... 
	20	a : 0
queue:	30	c : 1	[from a:=0]
	20	a : X
	30	c : X	[by a:=X]
should suppress c+ weak unstable 
c should still become X 
	30	a : 0
	40	c : 1	[by a:=0]
	40	a : 1
	40	b : 1
queue:	50	c : 0	[from b:=1]
WARNING: weak-unstable `c'-
rule: [after 10]	b:X -> c-:1
>> cause: `b' (val: X)
	40	b : X
	50	c : X	[by b:=X]
should report c- weak unstable 
c should still become X 
