view demo/roundTrip.ur @ 1595:154cfe2eb366

Better error messages about server-side use of client-side functions
author Adam Chlipala <adam@chlipala.net>
date Mon, 14 Nov 2011 09:15:10 -0500
parents ed06e25c70ef
children
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table channels : { Client : client, Channel : channel (string * int * float) }
  PRIMARY KEY Client

fun writeBack v =
    me <- self;
    r <- oneRow (SELECT channels.Channel FROM channels WHERE channels.Client = {[me]});
    send r.Channels.Channel v

fun action () =
    me <- self;
    ch <- channel;
    dml (INSERT INTO channels (Client, Channel) VALUES ({[me]}, {[ch]}));
    
    buf <- Buffer.create;

    let
        fun receiver () =
            v <- recv ch;
            Buffer.write buf ("(" ^ v.1 ^ ", " ^ show v.2 ^ ", " ^ show v.3 ^ ")");
            receiver ()

        fun sender s n f =
            sleep 2000;
            rpc (writeBack (s, n, f));
            sender (s ^ "!") (n + 1) (f + 1.23)
    in
        return <xml><body onload={spawn (receiver ()); sender "" 0 0.0}>
          <dyn signal={Buffer.render buf}/>
        </body></xml>
    end

fun main () = return <xml><body>
  <form><submit value="Begin demo" action={action}/></form>
</body></xml>