NLC error

ERROR: Message 'includes' not understood.
RECEIVER:
   nil
ARGS:
   Symbol 'out'
CALL STACK:
	DoesNotUnderstandError:reportError   0x1138e8298
		arg this = <instance of DoesNotUnderstandError>
	Nil:handleError   0x1138f1078
		arg this = nil
		arg error = <instance of DoesNotUnderstandError>
	Thread:handleError   0x113963098
		arg this = <instance of Thread>
		arg error = <instance of DoesNotUnderstandError>
	Object:throw   0x11541f9f8
		arg this = <instance of DoesNotUnderstandError>
	Object:doesNotUnderstand   0x11541f948
		arg this = nil
		arg selector = 'includes'
		arg args = [*1]
	NLC_BaseElement:initData   0x11459fa38
		arg this = <instance of NLC_MasksElement>
		arg synth = <instance of SynthDef>
		var innerLabels = [*1]
		var innerParameters = [*1]
		var argumentNames = nil
		var synthParameters = nil
		var template = <instance of SynthDef>
		var removalIndex = nil
	NLC_BaseElement:invokeData   0x1139253c8
		arg this = <instance of NLC_MasksElement>
		arg synth = <instance of SynthDef>
		arg patternType = 'Pbind'
	NLC_MetaElement:init   0x1145a01b8
		arg this = <instance of NLC_MasksElement>
		arg synth_ = <instance of SynthDef>
		arg name_ = 'sine'
		arg patternType_ = 'Pbind'
	NLC_Element:init   0x115416a08
		arg this = <instance of NLC_Element>
		arg patternType_ = 'Pbind'
	< closed FunctionDef >  (no arguments or variables)
	Interpreter:interpretPrintCmdLine   0x114897058
		arg this = <instance of Interpreter>
		var res = nil
		var func = <instance of Function>
		var code = "(
x =  SynthDef(\test, {|fre..."
		var doc = nil
		var ideClass = <instance of Meta_ScIDE>
	Process:interpretPrintCmdLine   0x112d9ed48
		arg this = <instance of Main>
^^ The preceding error dump is for ERROR: Message 'includes' not understood.
RECEIVER: nil