define(_,`dnl')_
define(__)_
define(____)_
define(______)_
_
define(Succ,_
__`if(iszero($1),_
____`(1,())',_
____`if(eq(head($1),0),_
______`(1,tail($1))',_
______`(0,Succ(tail($1)))')')')_
_
define(headswitch1of1,_
__`define($1,`_$1(head(''$1``))(''$1``)')'_
__`define(_$1,`$1_''$1``')')_
define(dol,`$$1')_