1: include "std"; 2: val v = 1,2,(3,4); 3: match (v) with 4: | (?x,_,?z) => 5: { 6: print x; 7: print ", "; 8: match (z) with 9: | (?a,?b) => 10: { 11: print "("; 12: print a; 13: print ", "; 14: print b; 15: print ")"; 16: } 17: endmatch; 18: } 19: endmatch; 20: endl;