CR{a=1,b=True}
CR{a=2,b=False}
CR{a=10,b=True}
CR{a=10,b=False}
CRR{r=CR{a=999,b=True},a=True}
2
False
1
1
True
1
1
True
S1 10
S2 20 "foo"
S1 99
S2 88 "foo"
S2 20 "bar"
999
2
1
888
2
777
2
CR{a=333,b=True}
10
20
10
20