{}.play on a UGen stored in variable?

Questions
1

Hi. This might be very newbie question, but I would really like to know why the second example does not produce sound despite ‘running’ on server.

// works (instance in the plotTree, sound:
c = {SinOsc.ar};
c.play;

// UGen instance in the plotTree, but no sound:
c = SinOsc.ar;
{c}.play;

Does the second example for some reason not create Out.ar? How can I see the precise message sent to server by the second example (that would enable me to debug this question myself)?

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2

All UGens must be created within the function.

You can never create the UGen outside the function and reference it within.

hjh

3

yes, that makes sense.
thank you!

4

As an add-on: though, from the ugenGraphFunction you can reference to a Function that generates a UGen, which enables nice live-coding options.

https://www.listarc.bham.ac.uk/lists/sc-users-2012/msg22935.html

5

Right, I had forgotten that:

c = SinOsc.ar;
{c}.play;  // not OK

c = { SinOsc.ar };
// now 'c' is not a UGen
// it's an instruction to create a UGen

{ c.value }.play;  // run the instruction *in* a synth function - OK

{ c }.play;  // also OK

The last one is OK because the function ‘c’ is automatically evaluated, when it’s used as an input to another UGen.

hjh

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6

SynthDef*-wrap is another way of injecting functions into SynthDefs - https://doc.sccode.org/Classes/SynthDef.html#*wrap. Not entirely related but I found this far too late when I was learning SC.

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