"{ Package: 'stx:libbasic2' }"

"{ NameSpace: Smalltalk }"

IteratorStream subclass:#RecursiveSeriesStream
	instanceVariableNames:'lastValue'
	classVariableNames:''
	poolDictionaries:''
	category:'Streams'
!

!RecursiveSeriesStream class methodsFor:'documentation'!

documentation
"
    documentation to be added.

    class:
        <a short class summary here, describing what instances represent>

    responsibilities:    
        <describing what my main role is>

    collaborators:    
        <describing with whom and how I talk to>

    API:
        <public api and main messages>
        
    example:
        <a one-line examples on how to use - can also be in a separate example method>

    implementation:
        <implementation points>

    [author:]
        cg

    [instance variables:]

    [class variables:]

    [see also:]

"
!

example
"
        |s|

        s := RecursiveSeriesStream on:[:n | n/2] startValue:1.
        s next:10.
        s next:10.

        s := RecursiveSeriesStream on:[:n | n even ifTrue:[n/2] ifFalse:[n*3+1]] startValue:10.
        s next:10.
        s next:10.
"
!

example2
"
        |s|

        1 to:100 collect:[:n0 |
                s := RecursiveSeriesStream on:[:n | n even ifTrue:[n/2] ifFalse:[n*3+1]] startValue:n0.
                s next:10.   
        ]
"
! !

!RecursiveSeriesStream class methodsFor:'instance creation'!

on:aBlock startValue:startValue
    ^ self basicNew initialize iterator:aBlock startValue:startValue
! !

!RecursiveSeriesStream methodsFor:'accessing'!

iterator:aOneArgBlock startValue:startValue
    iterator := aOneArgBlock.
    lastValue := startValue.
! !

!RecursiveSeriesStream methodsFor:'reading'!

next
    "return the next element from the stream by evaluating the nextBlock"

    |prevValue|

    prevValue := lastValue.
    lastValue := iterator value:lastValue.
    ^ prevValue

! !

!RecursiveSeriesStream class methodsFor:'documentation'!

version_CVS
    ^ '$Header$'
! !