x0 TY LISTNAT x1 x0 x2 TH LISTNAT _generated,List x3 x1 x2 x4 x0 x5 TH LISTNAT app_cons x6 TH LISTNAT app_nil x7 x4 x5 x6 x8 x3 x7 app_nil2 x8 x10 x0 x11 x10 x2 x12 x11 x13 x12 x14 x13 x15 x14 x16 x15 x17 x16 x18 x17 x7 app_assoc x18 app_assoc x7 x2 app_nil2 x0