Mercurial > urweb
annotate demo/listEdit.ur @ 726:6fc633d990e7
onError
author | Adam Chlipala <adamc@hcoop.net> |
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date | Thu, 16 Apr 2009 12:36:01 -0400 |
parents | fb2a0e76dcef |
children | e6bc6bbd7a32 |
rev | line source |
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adamc@646 | 1 datatype rlist = Nil | Cons of {Data : source string, |
adamc@646 | 2 NewData : source string, |
adamc@646 | 3 Tail : source rlist} |
adamc@646 | 4 |
adamc@646 | 5 fun showString ss = |
adamc@646 | 6 s <- signal ss; |
adamc@646 | 7 return <xml>{[s]}</xml> |
adamc@646 | 8 |
adamc@646 | 9 fun show rls = |
adamc@646 | 10 v <- signal rls; |
adamc@646 | 11 show' v |
adamc@646 | 12 |
adamc@646 | 13 and show' rl = |
adamc@646 | 14 case rl of |
adamc@646 | 15 Nil => return <xml/> |
adamc@646 | 16 | Cons {Data = ss, NewData = ss', Tail = rls} => return <xml> |
adamc@646 | 17 <dyn signal={showString ss}/> |
adamc@646 | 18 <button value="Change to:" onclick={s <- get ss'; set ss s}/> |
adamc@646 | 19 <ctextbox source={ss'}/><br/> |
adamc@646 | 20 <dyn signal={show rls}/> |
adamc@646 | 21 </xml> |
adamc@646 | 22 |
adamc@646 | 23 fun main () = |
adamc@646 | 24 head <- source Nil; |
adamc@646 | 25 tailP <- source head; |
adamc@646 | 26 data <- source ""; |
adamc@646 | 27 |
adamc@646 | 28 let |
adamc@646 | 29 fun add () = |
adamc@646 | 30 data <- get data; |
adamc@646 | 31 data <- source data; |
adamc@646 | 32 ndata <- source ""; |
adamc@646 | 33 tail <- get tailP; |
adamc@646 | 34 tail' <- source Nil; |
adamc@646 | 35 |
adamc@646 | 36 let |
adamc@646 | 37 val cons = Cons {Data = data, NewData = ndata, Tail = tail'} |
adamc@646 | 38 in |
adamc@646 | 39 set tail cons; |
adamc@646 | 40 set tailP tail'; |
adamc@646 | 41 |
adamc@646 | 42 head' <- get head; |
adamc@646 | 43 case head' of |
adamc@646 | 44 Nil => set head cons |
adamc@646 | 45 | _ => return () |
adamc@646 | 46 end |
adamc@646 | 47 in |
adamc@646 | 48 return <xml><body> |
adamc@646 | 49 <ctextbox source={data}/> <button value="Add" onclick={add ()}/><br/> |
adamc@646 | 50 <br/> |
adamc@646 | 51 |
adamc@646 | 52 <dyn signal={show head}/> |
adamc@646 | 53 </body></xml> |
adamc@646 | 54 end |