Why is this interpreter variable not understood?

Question

I'm trying to loosely-couple OSC message bindings to the function that handles them:

f = {|msg| msg.postln};
OSCFunc({|msg, time, addr, recvPort| f(msg)}, '/2/push1')

I thought this was pretty straightforward. I could substitute f at any point, and therefore muck about the handling of messages from the path /2/push1 at will.

But when I hit the button (sending a message with path /2/push1), I get an error saying:

Message 'f' not understood.

So I'm guessing f has a different meaning within the scope of the function declared in the call to OSCFunc. I guess it has a different Environment?

I also tried putting the function in a regular variable:

(
var myFunction = {|msg| msg.postln};
OSCFunc({|msg, time, addr, recvPort| myFunction(msg)}, '/2/push2');
)

But this results in the same error.

Is there a way around this? Surely I don't have to place an entire function body within OSCFunc every time?

Answer 1

No, your problem is just a SuperCollider syntax issue - it lies in what you've written here:

  f(msg)

I think that you're hoping this "invokes" the function f with msg as an argument. However, SuperCollider's syntax isn't quite like that - it actually interprets that as being an equivalent way of calling msg.f(), which is why it throws an error saying that msg knows no f message. Instead, you need to use the value message on your Function:

  f.value(msg)

I can't find a tutorial that spells this out right now, so instead here's a link to the Function helpfile.

Answer 2

I Googled around and found this:

f = {|msg, time, addr, recvPort| msg.postln};
o = OSCFunc(f, '/2/push1');

This works fine. Notice also the assignment of the call to OSCFunc to a variable. This enables me to 'de-register' the binding by calling:

o.free;