Class { #name : #DiyaRootNode, #superclass : #DiyaNode, #classVars : [ 'singleton' ], #category : #'Diya-Graphics' } { #category : #'instance creation' } DiyaRootNode class >> new [ self error: 'Please use uniqueInstance' ] { #category : #'instance creation' } DiyaRootNode class >> reset [ singleton := nil ] { #category : #'instance creation' } DiyaRootNode class >> uniqueInstance [ singleton ifNil: [ singleton := super new]. ^singleton ] { #category : #initialization } DiyaRootNode >> initialize [ super initialize. parent := self. ]