a        at  3:1 is a value bound here
x        at  4:7 is a value bound here
y        at  5:7 is a value bound here
t        at  7:7 is a value bound here
x        at 7:11 is a local value defined at 4:7
x        at 7:11 is a local value defined at 4:7
y        at 7:13 is a local value defined at 9:7
y        at 7:13 is a local value defined at 9:7
z        at 7:15 is a local value defined at 8:7
z        at 7:15 is a local value defined at 8:7
t        at 7:17 is a local value defined at 7:7
t        at 7:17 is a local value defined at 7:7
z        at  8:7 is a value bound here
y        at  9:7 is a value bound here
x        at 10:6 is a local value defined at 4:7
x        at 10:6 is a local value defined at 4:7
y        at 10:8 is a local value defined at 9:7
y        at 10:8 is a local value defined at 9:7
z        at 10:10 is a local value defined at 8:7
z        at 10:10 is a local value defined at 8:7