(define cartesian-product
   {(list A) --> (list A) --> (list (list A))}  
   [ ] _ -> [ ]  
   [X | Y] Z  -> (append (pair X Z) (cartesian-product Y Z)))

(define pair  
   {A --> (list A) --> (list (list A))}
   _ [ ] -> [ ]  
   X [Y | Z] -> [[X Y] | (pair X Z)]) 

(define converge* 
   {(A --> A) --> A --> (A --> A --> boolean) --> A}
   F X R -> (converge-help F (F X) X R))

(define converge-help  
   {(A --> A) --> A --> A --> (A --> A --> boolean) --> A}
   _ New Old R -> New  			where (R Old New)  
   F New _ R -> (converge-help F (F New) New R))
   
"(define cartesian-product
   {(list A) --> (list B) --> (list (A * B))}  
   [ ] _ -> [ ]  
   [X | Y] Z  -> (append (pair X Z) (cartesian-product Y Z)))

(define pair  
   {A --> (list B) --> (list (A * B))}
   _ [ ] -> [ ]  
   X [Y | Z] -> [(@p X Y) | (pair X Z)])"