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comparison demo/noisy.ur @ 651:bab524996fca

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Noisy demo
author Adam Chlipala <adamc@hcoop.net>
date Tue, 10 Mar 2009 17:29:03 -0400
parents
children 1a317a707d71
comparison
equal deleted inserted replaced
650:fcf0bd3d1667 651:bab524996fca
1 datatype list t = Nil | Cons of t * list t
2
3 table t : { Id : int, A : string }
4
5 fun add id s =
6 dml (INSERT INTO t (Id, A) VALUES ({[id]}, {[s]}))
7
8 fun del id =
9 dml (DELETE FROM t WHERE t.Id = {[id]})
10
11 fun lookup id =
12 ro <- oneOrNoRows (SELECT t.A FROM t WHERE t.Id = {[id]});
13 case ro of
14 None => return None
15 | Some r => return (Some r.T.A)
16
17 fun check ls =
18 case ls of
19 Nil => return ()
20 | Cons (id, ls') =>
21 ao <- lookup id;
22 alert (case ao of
23 None => "Nada"
24 | Some a => a);
25 check ls'
26
27 fun main () =
28 idAdd <- source "";
29 aAdd <- source "";
30
31 idDel <- source "";
32
33 return <xml><body>
34 <button value="Check values of 1, 2, and 3" onclick={check (Cons (1, Cons (2, Cons (3, Nil))))}/><br/>
35 <br/>
36 <button value="Add" onclick={id <- get idAdd; a <- get aAdd; add (readError id) a}/>
37 <ctextbox source={idAdd}/>
38 <ctextbox source={aAdd}/><br/>
39 <br/>
40 <button value="Delete" onclick={id <- get idDel; del (readError id)}/>
41 <ctextbox source={idDel}/>
42 </body></xml>