Arrows   at 1:14 is none
x        at  4:1 is a value bound here
y        at  4:3 is a value bound here
z        at 4:12 is a value bound here
a        at  5:3 is a value bound here
y        at  5:8 is a local value defined at 4:3
y        at  5:8 is a local value defined at 4:3
z        at 5:13 is a local value defined at 4:12
z        at 5:13 is a local value defined at 4:12
b        at  6:3 is a value bound here
y        at  6:8 is a local value defined at 4:3
y        at  6:8 is a local value defined at 4:3
a        at 6:13 is a local value defined at 5:3
a        at 6:13 is a local value defined at 5:3
y        at  7:3 is a local value defined at 4:3
y        at  7:3 is a local value defined at 4:3
b        at  7:8 is a local value defined at 6:3
b        at  7:8 is a local value defined at 6:3