1 Collection traits define: #Stream &parents: {PositionableStream} &slots: {#collection}.
2 "Collection Streams allow accessing of and writing into Collections like any
3 other Stream terminal."
5 s@(Collection Stream traits) terminal [s collection].
7 s@(Collection Stream traits) contents
8 "Answer the Stream's contents, in the default case the collection itself."
13 s@(Collection Stream traits) close
14 "Closes the link between the Stream and the Collection and resets it,
15 returning the Collection."
17 result ::= s collection.
23 s@(Collection Stream traits) hasAnEnd
24 "All Collections are finite, so Streams over them have an end."
27 s@(Collection Stream traits) collectionType
30 streamBlock@(Method traits) writingInto: c@(Collection traits)
31 "Create a new WriteStream for the given collection and apply the block to it,
32 answering the contents once done."
35 streamBlock applyWith: stream.
39 streamBlock@(Method traits) writingAs: c@(Collection traits) &capacity: capacity
40 "Create a new WriteStream for a new collection like the given one and apply the
41 block to it, answering the contents once done."
43 streamBlock writingInto: (c new &capacity: capacity)
46 streamBlock@(Method traits) writingAs: s@(ReadStream traits) &capacity: capacity
48 (streamBlock writingAs: s contents new &capacity: capacity) reader
51 Collection traits define: #ReadStream
52 &parents: {Collection Stream. ReadStream}.
53 "The default kind of iterator, a slot on the shared traits of Collection."
55 ExtensibleCollection traits define: #WriteStream &parents: {WriteStream} &slots: {#collection}.
56 "A totally non-Positionable WriteStream variant which just maps the protocol
57 to Collection addition protocol."
59 ws@(ExtensibleCollection WriteStream traits) on: c
60 "Targets the collection."
66 ws@(ExtensibleCollection WriteStream traits) contents
71 ws@(ExtensibleCollection WriteStream traits) nextPut: obj
72 [ws collection add: obj].
74 ws@(ExtensibleCollection WriteStream traits) nextPutAll: c
75 [ws collection addAll: c].
77 ws@(ExtensibleCollection WriteStream traits) next: n putAll: seq startingAt: start
79 ws collection addAll: (seq sliceFrom: start)
82 ws@(ExtensibleCollection WriteStream traits) close
83 "Closes the link between the Stream and the Collection and resets it."
85 result ::= ws collection.
90 ws@(ExtensibleCollection WriteStream traits) hasAnEnd [True].
92 ws@(ExtensibleCollection WriteStream traits) isAtEnd
93 "This type of stream cannot write over the contents and is perpetually
94 `at the end' of the contents, adding new elements."
97 c@(Collection traits) iterator
98 "Syntactic sugar for getting a new ReadStream or ReadWriteStream over the
99 given Collection that respects the same type."
102 c@(Collection traits) reader
103 "Syntactic sugar for getting a new ReadStream onto the given Collection
104 that respects the same type."
105 [c ReadStream newOn: c].
107 c@(Collection traits) writer
108 "Syntactic sugar for getting a new WriteStream onto the given Collection
109 that respects the same type."
110 [c WriteStream newOn: c].
112 cols@(Collection traits) iterators
113 "Returns a Collection of ReadStreams on the those in the given one. The
114 argument collection cannot contain non-collections."
116 cols collect: #iterator `er into: Array
119 cols@(Sequence traits) allDo: block
120 "Apply a coordinated do: over all of the collections in the given one,
123 iterators ::= cols iterators.
124 args ::= Array newSizeOf: iterators.
125 [iterators anySatisfy: #isAtEnd `er]
127 [iterators collect: #next `er into: args.
128 block applyTo: args].
131 x@(Collection traits) with: y@(Collection traits) do: block
132 [{x. y} allDo: block].
134 cols@(Sequence traits) allCollect: block into: result
135 "Uses allDo: to perform a collect: over the Sequence's Collections' elements,
136 using a stream in between."
137 [[| :result | cols allDo: [| *vals | result nextPut: (block applyTo: vals)]]
141 cols@(Sequence traits) allCollect: block
142 "Perform allCollect:into: using the Sequence as the result template."
143 [cols allCollect: block into: cols].
145 cols@(Sequence traits) streamAllCollect: block
147 [(cols iterators collect: #next`er)
148 reader collect: [| *rest | block applyTo: rest]]
152 x@(Collection traits) with: y@(Collection traits) collect: block
153 [{x. y} allCollect: block].
155 cols@(Sequence traits) zip
156 "Uses allCollect: to gather all the collection's collections' elements into
157 one collection. In other words, zip means to turn a pair of lists into
158 a list of pairs (for general values of 'pair')."
159 [cols allCollect: [| *vals | vals]].
161 cols@(Sequence traits) unzip
162 "Transposes a sequence of collection into a collection of sequences of those
163 elements across them, using a collection of streams and running with:do:
164 across the collection-result mapping. In other words, unzip means to turn a
165 list of pairs into a pair of lists (for general values of 'pair')."
167 results ::= cols first collect: [| :_ | cols newSameSize writer].
169 [| :col | col with: results do: [| :val :result | result nextPut: val]].
170 results collect: #contents `er
173 cols@(Sequence traits) allInject: start into: block
174 "Runs inject:into: across all the given collection's collections' elements."
177 cols allDo: [| *vals | result := block applyTo: (vals copyWith: result at: 0)].
181 source@(Root traits) streamInto: target
182 "Totally generic method for streaming the contents of one thing into another."
184 source reader >> target writer
187 source@(Root traits) streamFrom: target
189 target streamInto: source
192 cols@(Sequence traits) combinationsDo: block
193 "This performs a basic increment-with-carry across the iterators until
194 they are exhausted. The block is applied to all intermediate results."
196 ((iterators ::= cols iterators) anySatisfy: #isAtEnd `er)
198 values ::= iterators collect: #next `er .
199 block applyTo: values.
200 [position := iterators indexLast.
201 eachIterator := iterators at: position.
202 [eachIterator isAtEnd /\ [position > 0]]
205 values at: position put: eachIterator next.
207 eachIterator := iterators at: position].
208 eachIterator isAtEnd /\ [position isZero]
212 [values at: position put: eachIterator next].
213 block applyTo: values] loop
216 cols@(Sequence traits) combinationsCollect: block into: result
217 "Uses combinationsDo: to perform a collect: over all combinations of elements from the
218 Collections in the Sequence, using a stream in between."
219 [[| :result | cols combinationsDo: [| *vals | result nextPut: (block applyTo: vals)]]
223 cols@(Sequence traits) combinationsCollect: block
224 "Perform combinationsCollect:into: using the Sequence as the result template."
225 [cols combinationsCollect: block into: cols].
227 cols@(Sequence traits) combinationsInject: start into: block
228 "Runs inject:into: across all the combinations of the given Sequence's Collections' elements."
231 cols combinationsDo: [| *vals | result := block applyTo: (vals copyWith: result at: 0)].
235 Set traits define: #ReadStream &parents: {Collection ReadStream} &slots: {
236 #collection -> Set new.
237 #position -> 0. "The number of elements passed so far."
238 #index -> 0. "The index into the Set's contents Array."
240 "Set ReadStreams are just Positionable- over the element order in the Set's
241 contents Array. They're not very efficient, having to check for Nil's."
243 i@(Set ReadStream traits) on: c
244 "Retargets to the new Set, and resets position, etc."
245 [i `>> [collection := c. position := 0. index := 0. ]].
247 i@(Set ReadStream traits) next
248 "Increment the index through the array until a non-Nil element is reached.
249 This is poor for sparse Sets."
251 (i collection contents indexOfFirstSatisfying: [| :x | x isNotNil] startingAt: i index)
255 i index := nextIndex + 1.
256 i position := i position + 1.
257 i collection contents at: nextIndex]
260 i@(Set ReadStream traits) next: n putInto: seq startingAt: start
261 [| numRead nextIndex |
263 contents ::= i collection contents.
264 nextIndex := i index.
266 [(nextIndex := contents indexOfFirstSatisfying: #isNotNil `er startingAt: i index) isNil] whileFalse:
267 [i index := nextIndex + 1.
269 seq at: seqIndex put: (contents at: nextIndex).
275 i@(Set ReadStream traits) isAtEnd
276 "Checks both the Set size and then the underlying Array index, since a sparse
277 Set would reach the first before the second."
279 i position = i collection size \/ [i index = i collection contents indexLast]
282 Sequence traits define: #Stream &parents: {PositionableStream} &slots: {#collection -> ExtensibleArray new}.
283 "A Stream over a Sequence, where the position corresponds to the index within
286 s@(Sequence Stream traits) on: c
287 "Target the stream to the specific collection, and reset the indices."
288 [s `>> [reset. collection := c. readLimit := c size. ]].
290 s@(Sequence Stream traits) contents
291 "Answer the contents of the target by copying, up to the limit."
293 s collection copyFrom: 0 below: s readLimit
296 s@(Sequence Stream traits) collectionType
299 s@(Sequence Stream traits) last
301 s collection at: s position
304 Sequence traits define: #ReadStream
305 &parents: {Sequence Stream. ReadStream}.
306 "A Stream used to read from a Sequence object."
308 s@(Stream traits) newFrom: obj
309 "A convenient method to override for creating new ReadStreams of the
310 appropriate type for a given type of object."
311 "NOTE: determine what overrides justify this since #reader is easier for nearly
313 [obj ReadStream newOn: obj].
315 rs@(Sequence ReadStream traits) next
317 (pos ::= rs position) < rs readLimit
319 [rs position := pos + 1.
320 rs collection at: pos]
321 ifFalse: [rs exhausted]
324 rs@(Sequence ReadStream traits) next: n
325 "Overridden for efficiency."
327 end ::= rs position + n min: rs readLimit.
328 result ::= rs collection copyFrom: rs position below: end.
333 rs@(Sequence ReadStream traits) next: n putInto: c startingAt: start
335 max ::= rs readLimit - rs position min: n.
336 c replaceFrom: start to: start + max - 1 with: rs collection startingAt: rs position.
341 rs@(Sequence ReadStream traits) peekAt: offset
343 rs collection at: rs position + offset
346 rs@(Sequence ReadStream traits) peek
349 rs@(Sequence ReadStream traits) peekBack
351 rs position isZero ifFalse: [rs position := rs position - 1. rs next]
354 rs@(Sequence ReadStream traits) nextPut: obj
355 "Sequence ReadStreams should not place elements into the stream."
358 rs@(Sequence ReadStream traits) size
359 "The limit is effectively the number of elements that can be collected."
364 rs@(Sequence ReadStream traits) upTo: obj
365 "Answer all the elements until the given object is reached."
367 start ::= rs position.
368 end ::= rs collection indexOf: obj startingAt: start ifAbsent:
369 [rs position := rs collection size. ^ (rs collection copyFrom: start)].
370 rs position := end + 1.
371 rs collection copyFrom: start below: end
374 rs@(Sequence ReadStream traits) upToEnd
375 "Answer all the elements up to the limit by a copy."
377 start ::= rs position.
378 rs position := rs collection size.
379 rs collection copyFrom: start below: rs position
382 rs@(Sequence ReadStream traits) on: c from: start to: end
383 "Target the stream on a particular slice of a collection."
384 [rs `>> [collection := c. readLimit := end min: c size. position := start. ]].
386 Sequence traits define: #WriteStream
387 &parents: {Sequence Stream. WriteStream}
388 &slots: {#writeLimit}.
390 s@(Stream traits) newTo: obj@(Sequence traits) &position: position
391 [obj WriteStream newOn: obj &position: position].
393 seq@(Sequence traits) writer &position: position
394 [seq WriteStream newOn: seq &position: position].
396 seq@(Sequence traits) appender
397 [seq WriteStream newOn: seq &position: seq size].
399 ws@(Sequence WriteStream traits) newOn: c &position: position
400 [ws clone on: c &position: position].
402 ws@(Sequence WriteStream traits) on: c &position: position
405 ws writeLimit := c size.
406 position ifNotNil: [ws position := position].
410 ws@(Sequence WriteStream traits) contents
412 ws readLimit := ws readLimit max: ws position.
413 ws collection copyFrom: 0 below: ws readLimit
416 ws@(Sequence WriteStream traits) next
419 ws@(Sequence WriteStream traits) growCollectionAtEnd &byAtLeast: minGrowth
422 newSize ::= c size + (c size min: 1000000 max: (minGrowth ifNil: [20])).
423 ws collection := c newSize: newSize.
424 ws collection replaceFrom: 0 to: c size - 1 with: c.
425 ws writeLimit := newSize.
428 ws@(Sequence WriteStream traits) pastEndPut: obj
430 ws growCollectionAtEnd.
431 ws collection at: ws position put: obj.
432 ws position := ws position + 1.
436 ws@(Sequence WriteStream traits) nextPut: obj
438 (pos ::= ws position) >= ws writeLimit
439 ifTrue: [ws pastEndPut: obj]
440 ifFalse: [ws position := pos + 1.
441 ws collection at: pos put: obj]
444 ws@(Sequence WriteStream traits) next: n putAll: c startingAt: start
446 (newEnd ::= ws position + n - 1) >= ws writeLimit ifTrue:
447 [ws growCollectionAtEnd &byAtLeast: newEnd - ws writeLimit + 4].
448 ws collection replaceFrom: ws position to: newEnd with: c startingAt: start.
449 ws position := newEnd + 1.
453 ws@(Sequence WriteStream traits) size
455 ws readLimit := ws readLimit max: ws position
458 ws@(Sequence WriteStream traits) position: n
460 ws readLimit := ws readLimit max: n.
465 ws@(Sequence WriteStream traits) newLine
466 "Output an appropriate newLine character."
467 "TODO: make this portable."
472 ws@(Sequence WriteStream traits) atBeginningOfLine
473 "Returns whether the stream is writing at a point where a line ending has
475 "TODO: make this portable."
477 (ws collection at: ws position - 1) = $\n
480 ws@(Sequence WriteStream traits) freshLine
481 "Output a newLine character character if not currently at the end of a line."
483 ws atBeginningOfLine ifFalse: [ws newLine]
486 ws@(Sequence WriteStream traits) reset
488 ws readLimit := ws readLimit max: ws position.
493 ws@(Sequence WriteStream traits) resetToStart
495 ws readLimit := ws position := 0.
499 ws@(Sequence WriteStream traits) setToEnd
501 ws position := ws size.
505 ws@(Sequence WriteStream traits) on: c from: start to: end
508 ws readLimit := ws writeLimit := end min: c size.
509 ws position := start.
513 ws@(Sequence WriteStream traits) peekLast
515 ws position ifNotNil: [ws contents at: position]
518 ws@(Sequence WriteStream traits) with: c
521 ws position := ws readLimit := ws writeLimit := c size.
525 Sequence traits define: #ReadWriteStream
526 &parents: {Sequence WriteStream. Sequence ReadStream}.
528 rws@(Sequence traits) iterator
530 rws ReadWriteStream newOn: rws
533 rws@(Sequence ReadWriteStream traits) contents
535 rws readLimit := rws readLimit max: rws position.
536 rws collection copyFrom: 0 below: rws readLimit
539 rws@(Sequence ReadWriteStream traits) next
541 (pos ::= rws position) >= rws readLimit
542 ifTrue: [rws exhausted]
543 ifFalse: [rws position := pos + 1.
544 rws collection at: pos]
547 rws@(Sequence ReadWriteStream traits) next: n
549 rws readLimit := rws readLimit max: rws position.
550 end ::= rws position + n min: rws readLimit.
551 result ::= rws collection copyFrom: rws position below: end.
556 rws@(Sequence ReadWriteStream traits) = rws2@(Sequence ReadWriteStream traits)
558 rws position = rws2 position /\ [rws contents = rws2 contents]
561 rws@(Sequence ReadWriteStream traits) hash
563 (rws isSameAs: Sequence ReadWriteStream) ifFalse: [^ resend].
564 (rws position + rws readLimit + 53) hash
567 ExtensibleSequence traits define: #WriteStream
568 &parents: {Sequence WriteStream}.
569 "A Stream used to write to a new or existing ExtensibleSequence."
571 ws@(ExtensibleSequence WriteStream traits) pastEndPut: obj
575 ws writeLimit := c size.
580 ws@(ExtensibleSequence WriteStream traits) next: n putAll: c startingAt: start
582 ws collection at: ws position insertAll: (c copyFrom: start below: start + n).
587 ExtensibleSequence traits define: #ReadWriteStream
588 &parents: {ExtensibleSequence WriteStream. ExtensibleSequence ReadStream}.