"{ Package: 'stx:goodies/xtreams/terminals' }"

"{ NameSpace: Xtreams }"

ReadStream subclass:#BlockClosureReadStream

	instanceVariableNames:'contentsSpecies closeBlock'

	classVariableNames:''

	poolDictionaries:''

	category:'Xtreams-Terminals'

!

BlockClosureReadStream comment:'Read stream on a zero argument block, evaluates the block once for each requested element, the result of the block evaluation is the element.

{{{

	"inifinite stream of ones"

	[ 1 ] reading read: 20

}}}

{{{

	"Fibonacci"

	| a b | a := 0. b := 1.

	[ | x | x := a. a := b. b := x + a. x ] reading ++ 500; get

}}}

{{{

	"Streaming over ObjectMemory"

	x := ObjectMemory someObject.

	[ x := ObjectMemory nextObjectAfter: x ] reading read: 5

}}}

Instance Variables

	contentsSpecies	<Class> species for collections of elements of this stream

	closeBlock	<BlockClosure> invoked in response to the #close message, allows customizing the close behavior

'

!

!BlockClosureReadStream methodsFor:'accessing'!

get

	^source value

!

read: anInteger into: aSequenceableCollection at: startIndex

	| count |

	count := 0.

	[[count < anInteger] whileTrue:

		[aSequenceableCollection at: startIndex + count put: source value.

		count := count + 1]]

			on: Incomplete do: [(Incomplete on: aSequenceableCollection count: count at: startIndex) raise].

	^anInteger

! !

!BlockClosureReadStream methodsFor:'initialize-release'!

close

	closeBlock cull: self

!

closeBlock

	^closeBlock

!

closeBlock: aBlock

	closeBlock := aBlock

!

contentsSpecies

	^contentsSpecies

!

contentsSpecies: anObject

	contentsSpecies := anObject

!

on: aBlockClosure

	super on: aBlockClosure.

	contentsSpecies := Array.

	closeBlock := []

! !

!BlockClosureReadStream class methodsFor:'documentation'!

version_SVN

    ^ '$Id$'

! !