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|
fun isBeppo (s : string) : transaction string =
case s of
"Beppo" => return "Yup, that's him!"
| "Mephisto" => error <xml>Great googely moogely!</xml>
| _ => return "Who's that?"
fun listOf (n : int) =
if n < 0 then
error <xml>Negative!</xml>
else if n = 0 then
return []
else
ls <- listOf (n - 1);
return (n :: ls)
fun length ls =
case ls of
[] => 0
| _ :: ls' => 1 + length ls'
fun main () : transaction page =
s <- source "";
ns <- source "";
return <xml><body>
<ctextbox source={s}/>
<button value="rpc" onclick={fn _ => v <- get s;
r <- rpc (isBeppo v);
alert r}/>
<button value="tryRpc" onclick={fn _ => v <- get s;
r <- tryRpc (isBeppo v);
case r of
None => alert "Faaaaaailure."
| Some r => alert ("Success: " ^ r)}/>
<hr/>
<ctextbox source={ns}/>
<button value="rpc" onclick={fn _ => v <- get ns;
r <- rpc (listOf (readError v));
alert (show (length r))}/>
<button value="tryRpc" onclick={fn _ => v <- get ns;
r <- tryRpc (listOf (readError v));
case r of
None => alert "Faaaaaailure."
| Some r => alert ("Success: " ^ show (length r))}/>
</body></xml>
|
