Object subclass: #Interval
	instanceVariableNames: 'current start stop step'.

Interval class methodsFor: 'creating'

start: aStart stop: aStop step: aStep
	^(self new) 
		start: aStart;
		stop: aStop;
		step: aStep;
		yourself

Interval methodsFor: 'private'

start: anObject
	start := anObject.
	current := anObject.
	
stop: anObject
	stop := anObject.

step: anObject
	step := anObject.
	
Interval methodsFor: 'accessing'

hasNext
	^current <= stop
	
next
	| tmp |
	tmp = current.
	self hasNext ifTrue: [
		current := current + step ].
	^tmp
	

"Main!"

| interval |
interval := Interval start: 1 stop: 100 step: 10.
[ interval hasNext ] whileTrue: [
	Transcript show: interval next ].