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

"{ NameSpace: Xtreams }"

WriteStream subclass:#SequenceableCollectionWriteStream

	instanceVariableNames:'position length'

	classVariableNames:''

	poolDictionaries:'XtreamsPool'

	category:'Xtreams-Terminals'

!

SequenceableCollectionWriteStream comment:'Write stream on a sequenceable collection. The collection is grown automatically to accommodate any elements written. Closing a collection write stream will truncate the collection to the current stream position. This behavior is useful as a replacement for the traditional #contents message. The contents can be accessed with the #terminal message after the stream is closed.

{{{

	String new writing write: ''Hello World''; -- 6; close; terminal

}}}

Instance Variables

	position        <Integer> current position of the stream

	length  <Integer> number of valid elements in the destination

'

!

!SequenceableCollectionWriteStream methodsFor:'accessing'!

contents

	^destination copyFrom: 1 to: position

!

insert: anInteger from: aSequenceableCollection at: startIndex

	destination := destination copyGrownToAtLeast: destination size + anInteger.

	destination replaceFrom: position + anInteger + 1 to: length + anInteger with: destination startingAt: position + 1.

	destination replaceFrom: position + 1 to: position + anInteger with: aSequenceableCollection startingAt: startIndex.

	position := position + anInteger.

	length := length + anInteger.

	^anInteger

!

put: anObject

	| free |

	free := destination size - position.

	free < 1 ifTrue: [destination := destination copyGrownToAtLeast: destination size + 1].

	position := position + 1.

	destination at: position put: anObject.

	length := length + 1.

	^anObject

!

write: anInteger from: aSequenceableCollection at: startIndex

	| available |

	available := destination size - position.

	available < anInteger ifTrue: [destination := destination copyGrownToAtLeast: destination size + anInteger - available].

	destination replaceFrom: position + 1 to: position + anInteger with: aSequenceableCollection startingAt: startIndex.

	position := position + anInteger.

	position > length ifTrue: [length := position].

	^anInteger

! !

!SequenceableCollectionWriteStream methodsFor:'initialize-release'!

close

	destination := destination copyFrom: 1 to: position

!

contentsSpecies

	^destination species

!

flush

!

on: aSequenceableCollection

	super on: aSequenceableCollection.

	position := 0.

	length := 0

! !

!SequenceableCollectionWriteStream methodsFor:'printing'!

streamingPrintOn: aStream

	| tail head |

	super streamingPrintOn: aStream.

	tail := position min: 5.

	head := (destination size - position) min: (10 - tail).

	aStream

		write: ' position: ';

		print: position;

		write: ' size: ';

		print: destination size;

		cr; tab;

		write: (position > 5 ifTrue: ['...'] ifFalse: ['']);

		print: (destination copyFrom: position + 1 - tail to: position);

		write: '  |  ';

		print: (destination copyFrom: position + 1 to: position + head);

		write: (destination size - position > (10 - tail) ifTrue: ['...'] ifFalse: [''])

! !

!SequenceableCollectionWriteStream methodsFor:'private'!

streamingInsert: anInteger from: aStreamable

	| reading |

	reading := aStreamable reading.

	destination := destination copyGrownToAtLeast: destination size + anInteger.

	destination replaceFrom: position + anInteger to: destination size with: destination startingAt: position.

	[reading read: anInteger into: destination at: position + 1]

		on: Incomplete do: [:error | position := position + error count. error pass].

	position := position + anInteger

!

streamingInsertFrom: aStreamable

	self error: 'Not Yet Implemented'

!

streamingWrite: anInteger from: aReadStream

	| available |

	available := destination size - position.

	available < anInteger ifTrue: [destination := destination copyGrownToAtLeast: destination size + anInteger - available].

	[aReadStream read: anInteger into: destination at: position + 1]

		on: Incomplete do: [:error |

			position := position + error count.

			position > length ifTrue: [length := position].

			error pass].

	position := position + anInteger.

	position > length ifTrue: [length := position].

	^anInteger

!

streamingWriteFrom: aReadStream

	| available count chunkSize |

	count := 0.

	chunkSize := DefaultBufferSize.

	^[[available := destination size - position.

	available < chunkSize ifTrue: [destination := destination copyGrownToAtLeast: destination size + chunkSize].

	aReadStream read: chunkSize into: destination at: position + 1.

	position := position + chunkSize.

	count := count + chunkSize] repeat]

		on: Incomplete do: [:exception |

			position := position + exception count.

			position > length ifTrue: [length := position].

			count + exception count]

! !

!SequenceableCollectionWriteStream methodsFor:'seeking'!

++ anInteger

	| count |

	anInteger < 0 ifTrue: [ ^self -- anInteger negated ].

	count := self available min: anInteger.

	position := position + count.

	count < anInteger ifTrue: [(Incomplete count: count) raise].

	^anInteger

!

-- anInteger

	| count |

	anInteger < 0 ifTrue: [ ^self ++ anInteger negated ].

	count := position min: anInteger.

	position := position - count.

	count = anInteger ifTrue: [^anInteger].

	(Incomplete count: count) raise

!

length

	^length

!

position

	^position

!

position: aPosition

	aPosition < 0 ifTrue: [ Incomplete zero raise ].

	position := aPosition min: self length.

	position = aPosition ifTrue: [^aPosition].

	(Incomplete count: position) raise

! !

!SequenceableCollectionWriteStream methodsFor:'testing'!

isPositionable

	^true

! !

!SequenceableCollectionWriteStream class methodsFor:'documentation'!

version_HG

    ^ '$Changeset: <not expanded> $'

! !