Portability fixes
* do not use Object>>asString. Not all Smalltalks implement it.
* do not use Object>>name. Not all Smalltalks implement it.
* do not use Dictionary keysAndValuesRemove:. Not all Smalltalks implement it.
* do not use Class>>methods The semantics is different among Smalltalks.
Use `Class methodDictionary values` instead.
* do not modify dictionary in #at:ifAbsentPut: block!
"{ Package: 'stx:goodies/petitparser/compiler' }"
"{ NameSpace: Smalltalk }"
PPCNilNode subclass:#PPCSentinelNode
instanceVariableNames:''
classVariableNames:''
poolDictionaries:''
category:'PetitCompiler-Nodes'
!
PPCSentinelNode class instanceVariableNames:'Instance'
"
No other class instance variables are inherited by this class.
"
!
!PPCSentinelNode class methodsFor:'as yet unclassified'!
instance
^ Instance ifNil: [ Instance := self basicNew ]
! !