Ur/Web: tests/list.ur annotate

Some standard library additions from Edward Z. Yang

author	Adam Chlipala <adam@chlipala.net>
date	Sat, 19 May 2012 11:32:12 -0400
parents	9021d44ba6b2
children

rev	line source
adamc@757	1 fun isNil (t ::: Type) (ls : list t) =
adamc@757	2 case ls of
adamc@762	3 [] => True
adamc@757	4 \| _ => False
adamc@196	5
adamc@757	6 fun delist (ls : list string) : xbody =
adamc@757	7 case ls of
adamc@762	8 [] => <xml>Nil</xml>
adamc@762	9 \| h :: t => <xml>{[h]} :: {delist t}</xml>
adamc@196	10
adamc@758	11 fun callback ls = return <xml><body>
adamc@758	12 {delist ls}
adamc@758	13 </body></xml>
adamc@758	14
adamc@757	15 fun main () = return <xml><body>
adamc@762	16 {[isNil ([] : list bool)]},
adamc@762	17 {[isNil (1 :: [])]},
adamc@762	18 {[isNil ("A" :: "B" :: [])]}
adamc@196	19
adamc@762	20 <p>{delist ("X" :: "Y" :: "Z" :: [])}</p>
adamc@762	21 <a link={callback ("A" :: "B" :: [])}>Go!</a>
adamc@757	22 </body></xml>

Mercurial > urweb