fst
0
Z
nil
fst
s
X
cons
Y
Z
cons
Y
n__fst
activate
X
activate
Z
from
X
cons
X
n__from
s
X
add
0
X
X
add
s
X
Y
s
n__add
activate
X
Y
len
nil
0
len
cons
X
Z
s
n__len
activate
Z
fst
X1
X2
n__fst
X1
X2
from
X
n__from
X
add
X1
X2
n__add
X1
X2
len
X
n__len
X
activate
n__fst
X1
X2
fst
X1
X2
activate
n__from
X
from
X
activate
n__add
X1
X2
add
X1
X2
activate
n__len
X
len
X
activate
X
X
fst
2
0
0
nil
0
s
1
cons
2
n__fst
2
activate
1
from
1
n__from
1
add
2
n__add
2
len
1
n__len
1
INNERMOST
./TRS/TRCSR/Ex2_Luc03b_Z.trs