>
> Hello,
>
> I would like to propose the addition of method "update" for the
> Function class as follows:
>
> update { arg theChanged, theChanger;
> ^this.value(theChanged, theChanger);
> }
>
> This makes it possible to add a Function directly as dependant to
> any Object. This has the effect of radically generalizing and
> simplifying the usage of the Observer pattern: A Function can act
> as simple and direct "Adapter" to react to a change happening in
> any object that wishes to notify its dependants with:
>
this.changed(whatChanged, this)
>
> One of the many uses I have found for this is for example the
> ability to add functions to execute when a Server starts or quits,
> or when any Node or EventStreamPlayer ends (code attached). It is
> part of a small reliable scheme for broadcasting any changes in the
> run state of Nodes and EventStreamPlayers with any object that
> might need to be notification.
>
> If this could be included in
3.2 then I would like to document it
> in the upcoming sc-book.
>
> Iannis Zannos
>
>
> ======================================================================
> =
>
> onEnd { | argFunc |
> var cmdPeriodFunc;
> NodeWatcher.register(this);
> // this is needed to add this to catch synths stopped by
> Command-Period:
> cmdPeriodFunc = {
>
NodeWatcher.unregister(this);
> CmdPeriod.remove(cmdPeriodFunc);
> argFunc.value;
> };
> CmdPeriod.add(cmdPeriodFunc);
> // This evaluates argFunc when notified by NodeWatcher
> this.addDependant { | me, whatHappened |
> if (whatHappened == \n_end) {
> argFunc.(this);
> this.removeDependant(argFunc);
> // see CmdPeriod above
> CmdPeriod.remove (cmdPeriodFunc);
> }
> };
> }
> }
>
> + EventStreamPlayer {
> onEnd { | argFunc |
> this.addDependant
{ | me, whatHappened |
> if (whatHappened == \stopped) {
> argFunc.(this);
> this.removeDependant(argFunc);
> }
> }
> }
>