Replace `ifNil:[...]` with `isNil ifTrue:[...]`
The latter is optimized by compilers and therefore faster.
"{ Package: 'stx:goodies/petitparser/compiler/tests/extras' }"
"{ NameSpace: Smalltalk }"
PPCLRPNode subclass:#PPCLRPContainedElement
instanceVariableNames:'container'
classVariableNames:''
poolDictionaries:''
category:'PetitCompiler-Extras-Tests-LRP'
!
!PPCLRPContainedElement methodsFor:'accessing'!
container
^ container
!
container: anObject
container := anObject
! !
!PPCLRPContainedElement class methodsFor:'documentation'!
version_HG
^ '$Changeset: <not expanded> $'
! !