annotate tests/list.ur @ 324:b91480c9a729

More opportunities to use regions and lack of string copying
author Adam Chlipala <adamc@hcoop.net>
date Thu, 11 Sep 2008 13:06:51 -0400
parents 71bafe66dbe1
children fa2019a63ea4
rev   line source
adamc@196 1 datatype list a = Nil | Cons of a * list a
adamc@196 2
adamc@196 3 val isNil = fn t ::: Type => fn ls : list t =>
adamc@196 4 case ls of Nil => True | _ => False
adamc@196 5
adamc@196 6 val show = fn b => if b then "True" else "False"
adamc@196 7
adamc@196 8 val rec delist : list string -> xml body [] [] = fn x =>
adamc@196 9 case x of
adamc@196 10 Nil => <body>Nil</body>
adamc@196 11 | Cons (h, t) => <body>{cdata h} :: {delist t}</body>
adamc@196 12
adamc@196 13 val main : unit -> page = fn () => <html><body>
adamc@196 14 {cdata (show (isNil (Nil : list bool)))},
adamc@196 15 {cdata (show (isNil (Cons (1, Nil))))},
adamc@196 16 {cdata (show (isNil (Cons ("A", Cons ("B", Nil)))))}
adamc@196 17
adamc@196 18 <p>{delist (Cons ("X", Cons ("Y", Cons ("Z", Nil))))}</p>
adamc@196 19 </body></html>