mfp

    open Batteries

     type 'a tree = Leaf of 'a | Branch of 'a tree * 'a * 'a tree
	 deriving (Show)
     
     type point = { x : float; y : float }
	 deriving (Show)
     
     let points = Branch (Leaf {x=0.0;
				y=0.0;},
			  {x=2.0; y=2.0},
			  Branch (Leaf {x=1.0; y=1.0},
				  {x=1.0; y=0.0},
				  Leaf {x=0.0; y=1.0}))
    		      
    Show.show<point tree> points
    =>
    "Branch
       (Leaf {x =0.; y =0.}, {x =2.; y =2.},
	Branch
	  (Leaf {x =1.; y =1.}, {x =1.; y =0.}, Leaf {x =0.; y =1.}))"

    (* normal *) 
    let fib = function 0 | 1 -> 1 | n -> fib (n-1) + fib (n-2)
    (* memoized *)
    let fib = memo 0 | 1 -> 1 | n -> fib (n-1) + fib (n-2)

    type json mytype = Foo | Bar of int * int
    (* just add "json" to the type declaration to create to
       create the json_of_mytype and mytype_of_json functions *)

   TABLE user users
     COLUMN id SERIAL AUTO PRIMARY KEY
     COLUMN name VARCHAR(64) UNIQUE
     COLUMN age INT NULLABLE INDEXED
     COLUMN password VARCHAR(64)
   END
   
   TABLE comment comments
     COLUMN id SERIAL AUTO PRIMARY KEY
     COLUMN title TEXT
     COLUMN text TEXT
     COLUMN created_at TIMESTAMPZ
     COLUMN author SERIAL FOREIGN(users, id)
   END
   
   let minors x = SELECT [User_age < (Some 18)] x
   let pauls = SELECT [User_name LIKE "%Paul%"] users
   let young_pauls = minors pauls