What is the difference between List, Sequence, and Observable?

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Speaker. What is the difference between List, Sequence, and Observable? ӣߧળ

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SPEAKER ࣗѐ ӣߧળ - ઱۽ উ٘۽੉٘ܳ ѐߊ - ࣗ೐౟ਝয ݃ীझ౟۽ 6th ݭ౭ - ۨ੉פझ౟ উ٘۽੉٘ ѐߊ੗. - ো೤ زইܻ MashUp ױ੢. - ইఃఫ୛, FPী ҙब੉ ݆׮. - email : [email protected] - gitHub : https://github.com/omjoonkim - facebook : https://www.facebook.com/zkxns38

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WHAT?

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WHAT? List Sequence Observable

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WHAT? Method Chaining?

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WHAT? Method chaining, also known as named parameter idiom, is a common syntax for invoking multiple method calls in object- oriented programming languages

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WHAT? ߈ജ ч੉ Objectੋ ݫࣗ٘ܳ োࣘ੸ਵ۽ ࢎਊೞৈ ೐۽Ӓې߁ ೞח ੌ߈੸ੋ ҳޙ.

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WHAT? (1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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WHAT? List Sequence Observable

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WHY?

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য۵… WHY?

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ߑߨ਷.. ▸ ҕधകಕ੉૑, Documents ▸ StackOverFlow and Google god ▸ प೯ ࣽࢲ؀۽ ҳഅغয ੓ח ௏٘ өࠁӝ WHY?

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ߑߨ਷.. ▸ ҕधകಕ੉૑, Documents ▸ StackOverFlow and Google god ▸ प೯ ࣽࢲ؀۽ ҳഅغয ੓ח ௏٘ өࠁӝ WHY?

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੉੼? ▸ ղࠗ ҳഅਸ ࠆਵ۽ ॄ ੉ۿ + पઁ ҳഅ ੉೧о ೤୛ઉ ݺഛೞѱ ੉೧ о оӝ औ׮. ▸ ೧׼ API, Libraryܳ ѐߊೠ ࢎۈٜ੄ ࢸ҅ ੄ب, ӒܻҊ ௏٘झఋੌ ਸ ખ ؊ Ө੉ ੓ѱ ঌ ࣻ ੓׮. ▸ ௏٘ ੉೧۱੉ ֫ই૓׮. ▸ য়೑ ࣗझী ӝৈೡ ࣻ ੓ח ੄޷੓ח ୐ ߊ੗Ҵ! WHY?

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HOW?

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੉۠ ௏ٜ٘ਸ.. HOW? (1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } Observable.fromIterable(1..100) .map { it * 2 } .filter { it % 3 == 0 } .subscribe { println(it) }

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ਗې ߄۔਷.. HOW? class MergingSequence class SubSequence class TakeSequence class DropSequence class DistinctSequence

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ਗې ߄۔਷.. HOW? list.groupBy { it.from } .filter { it.key == KEY } .values .flatMap { it } .map { it.data } .flatMap { it } .forEach { println(it) } topicId .compose { loadBeforeComment.withLatestFrom(it, BiFunction { _, t2 -> t2 }) } .throttleFirst(1000, TimeUnit.MILLISECONDS) .flatMapMaybe { chatRepository.loadBeforeChat(it).neverError() } .bindToLifeCycle() .subscribe(successLoadChats)

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ೞ૑݅.. HOW?

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рױೞѱ! HOW? (1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } Observable.fromIterable(1..100) .map { it * 2 } .filter { it % 3 == 0 } .subscribe { println(it) }

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઱੄ ೡ੼ ▸ ௏٘ܳ ખ ؊ ӭՔೞѱ ࠁӝ ਤ೧ оदࢿ ߂ class ഑਷ method খױ ী ࠢח ఃਕٜ٘ਸ ઁѢೞ৓णפ׮. ▸ ௏٘ܳ ખ ؊ ӭՔೞѱ ࠁӝ ਤ೧ ਬਊೞҊ ੄޷ ੓ח Docsܳ ࢏ઁೞ ৓णפ׮. ▸ ݅ড पઁ۽ ௏٘ܳ ࠁन׮ݶ Docsܳ ࠁݶ ഻ঁ ੉೧ ೞӝ ए਋प Ѣীਃ! ▸ Observableэ਷ ҃਋ח दр࢚੄ ੉ਬ۽ о੢ рױೠ ColdStream ੄ ৘ઁ ௏٘۽ ഛੋೡ ৘੿ੑפ׮. HOW?

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LIST

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LIST੄ CHAINING਷.. LIST ݒ chain݃׮ ࢜۽਍ destination(ܻझ౟)ܳ ݅ ٜয chain੄ ೙ਃೠ ۈ׮ೣࣻܳ प೯ೠٍ Ѿҗчਸ destinationী ׸ই ׮਺ chainীѱ ֈѹ઱ח ߑध.

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LIST੄ CHAINING਷.. LIST LIST .ﬁlter() .map() .ﬂatMap() predicate() LIST LIST transform() transform() Source(1..100)

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(1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } ਋ܻо ࢓ಝࠅ ௏٘! LIST

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(1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } ਋ܻо ࢓ಝࠅ ௏٘! LIST

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } MAP? LIST

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } MAP? LIST

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } MAP? LIST map { listOf(it) }

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } MAP? LIST map { listOf(it) }

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } COLLECTIONSIZEORDEFAULT? LIST fun Iterable.collectionSizeOrDefault(default: Int): Int = if (this is Collection<*>) this.size else default

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } ੜࠁݶ ITERABLEী ഛ੢ ೣࣻ.. LIST fun Iterable.collectionSizeOrDefault(default: Int): Int = if (this is Collection<*>) this.size else default Progression Collection No Size

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fun Iterable.map(transform: (T) -> R): List { return mapTo( ArrayList(collectionSizeOrDefault(10)), transform ) } Ӓېࢲ ੉۠ ೣࣻо… LIST fun Iterable.collectionSizeOrDefault(default: Int): Int = if (this is Collection<*>) this.size else default

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׮द جইоࢲ.. MAPTO? LIST fun > Iterable.mapTo( destination: C, transform: (T) -> R ): C { for (item in this) destination.add(transform(item)) return destination }

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ࢤࢿ੗۽… LIST fun > Iterable.mapTo( destination: C, transform: (T) -> R ): C { for (item in this) destination.add(transform(item)) return destination }

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DESTINATIONী чਸ ֍যળ׮ LIST fun > Iterable.mapTo( destination: C, transform: (T) -> R ): C { for (item in this) destination.add(transform(item)) return destination }

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(1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } ਋ܻо ࢓ಝࠅ ௏٘! LIST

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FLATTEN? LIST fun Iterable>.flatten(): List { val result = ArrayList() for (element in this) { result.addAll(element) } return result }

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MATTO୊ۢ.. LIST fun Iterable>.flatten(): List { val result = ArrayList() for (element in this) { result.addAll(element) } return result }

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(1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } ਋ܻо ࢓ಝࠅ ௏٘! LIST

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FILTER? LIST fun Iterable.filter( predicate: (T) -> Boolean ): List { return filterTo(ArrayList(), predicate) }

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FILTER TO? LIST fun Iterable.filter( predicate: (T) -> Boolean ): List { return filterTo(ArrayList(), predicate) } fun > Iterable.filterTo( destination: C, predicate: (T) -> Boolean ): C { for (element in this) if (predicate(element)) destination.add(element) return destination }

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MATTO, FLATTEN੄ ࣻ೯ ߑधҗ э׮ LIST fun Iterable.filter( predicate: (T) -> Boolean ): List { return filterTo(ArrayList(), predicate) } fun > Iterable.filterTo( destination: C, predicate: (T) -> Boolean ): C { for (element in this) if (predicate(element)) destination.add(element) return destination }

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(1..100) .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) } ਋ܻо ࢓ಝࠅ ௏٘! LIST

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FOREACH? LIST fun Iterable.forEach(action: (T) -> Unit): Unit { for (element in this) action(element) }

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рױ! LIST fun Iterable.forEach(action: (T) -> Unit): Unit { for (element in this) action(element) }

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੿ܻೞݶ! LIST ܻझ౟ী ׸ӟ ؘ੉ఠо ݆ਸ ҃਋ method chainingߑधਸ ॳחѪ਷ दр੉ য়ې Ѧܾ ࣻ ੓׮. ژೠ ୭ઙ Ѿҗ઺ ౠ੿ чਸ ଺ਵ۰ ೡ ٸ  ژೠ ݽٚ elementী ؀ೠ chain੉ ՘աঠ݅ ഛੋೡ ࣻ ੓׮.

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SEQUENCE

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SEQUENCE੄ CHAINING਷.. SEQUENCE п chain݃׮ ঌݏ਷ Sequenceܳ ࢜۽ ٜ݅য ղݴ Terminal Sequence methodо ഐ୹ غ঻ਸ ٸ chain੄ ୐ Sequence੄ iteratorࠗఠ ࣽର੸ਵ۽ п chainػ Sequence੄ iterator੄ hasNext(), next()о ࣻ೯غয ୭ઙ Ѿҗޛਸ ߈ജೞח ߑध

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TERMINAL SEQUENCE? INTERMEDIATE SEQUENCE? SEQUENCE Terminal Sequence method: return ч੉ Sequence о ইצ Sequence੄ method Ex) toList(), find() , first() , etc… Intermediate Sequence method: return ч੉ Sequenceੋ Sequence੄ method Ex) map(), filter() , flatten() , etc…

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SEQUENCE੄ ҳࢿ SEQUENCE public interface Sequence { public operator fun iterator(): Iterator } public interface Iterator { public operator fun next(): T public operator fun hasNext(): Boolean }

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SEQUECNE੄ CHAINING਷.. SEQUENCE .ﬁlter() .map() .ﬂatMap() FILTERSEQUENCE predicate() Source(1..100) TRANSFORMING SEQUENCE FLATTENING SEQUENCE transform() transform() iterator iterator iterator

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OPERATOR KEYWORD SEQUENCE public interface Sequence { public operator fun iterator(): Iterator } public interface Iterator { public operator fun next(): T public operator fun hasNext(): Boolean } for (element in this) Terminate Sequence method о ഐ ୹ ؼ ٸ!

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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ASSQUENCE? SEQUENCE public fun Iterable.asSequence(): Sequence { return Sequence { this.iterator() } } Iterable to Sequence

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SEQUENCEܳ ࢤࢿೞח ׮ܲ ߑߨ SEQUENCE public fun generateSequence( seed: T?, nextFunction: (T) -> T? ): Sequence = if (seed == null) EmptySequence else GeneratorSequence({ seed }, nextFunction)

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SEQUENCEܳ ࢤࢿೞח ׮ܲ ߑߨ SEQUENCE public fun generateSequence( seed: T?, nextFunction: (T) -> T? ): Sequence = if (seed == null) EmptySequence else GeneratorSequence({ seed }, nextFunction)

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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MAP SEQUENCE public fun Sequence.map(transform: (T) -> R): Sequence { return TransformingSequence(this, transform) }

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MAP SEQUENCE public fun Sequence.map(transform: (T) -> R): Sequence { return TransformingSequence(this, transform) }

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MAP SEQUENCE public fun Sequence.map(transform: (T) -> R): Sequence { return TransformingSequence(this, transform) } (1..100).asSequence()

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TRANSFORMINGSEQUENCE SEQUENCE class TransformingSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() override fun next(): R { return transformer(iterator.next()) } override fun hasNext(): Boolean { return iterator.hasNext() } } fun flatten(iterator: (R) -> Iterator): Sequence { return FlatteningSequence( sequence, transformer, iterator ) } }

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߄۽ ੉੹ SEQUENCE SEQUENCE class TransformingSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() override fun next(): R { return transformer(iterator.next()) } override fun hasNext(): Boolean { return iterator.hasNext() } } fun flatten(iterator: (R) -> Iterator): Sequence { return FlatteningSequence( sequence, transformer, iterator ) } }

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ղࠗী ITERATORਸ о૑Ҋ ੓׮ SEQUENCE class TransformingSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() override fun next(): R { return transformer(iterator.next()) } override fun hasNext(): Boolean { return iterator.hasNext() } } fun flatten(iterator: (R) -> Iterator): Sequence { return FlatteningSequence( sequence, transformer, iterator ) } }

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TRANSFORMINGSEQUENCE੄ ITERATOR METHODী ҙৈ SEQUENCE class TransformingSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() override fun next(): R { return transformer(iterator.next()) } override fun hasNext(): Boolean { return iterator.hasNext() } } fun flatten(iterator: (R) -> Iterator): Sequence { return FlatteningSequence( sequence, transformer, iterator ) } }

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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FLATTEN SEQUENCE public fun Sequence>.flatten(): Sequence = flatten { it.iterator() }

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FLATTEN SEQUENCE fun Sequence.flatten( iterator: (T) -> Iterator ): Sequence { if (this is TransformingSequence<*, *>) { return (this as TransformingSequence<*, T>).flatten(iterator) } return FlatteningSequence(this, { it }, iterator) } public fun Sequence>.flatten(): Sequence = flatten { it.iterator() }

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ইө੹੄… SEQUENCE class TransformingSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() override fun next(): R { return transformer(iterator.next()) } override fun hasNext(): Boolean { return iterator.hasNext() } } fun flatten(iterator: (R) -> Iterator): Sequence { return FlatteningSequence( sequence, transformer, iterator ) } }

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FLATTENINGSEQUENCE… SEQUENCE internal class FlatteningSequence constructor( private val sequence: Sequence, private val transformer: (T) -> R, private val iterator: (R) -> Iterator ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() var itemIterator: Iterator? = null override fun next(): E { if (!ensureItemIterator()) throw NoSuchElementException() return itemIterator!!.next() } override fun hasNext(): Boolean { return ensureItemIterator() } private fun ensureItemIterator(): Boolean { if (itemIterator?.hasNext() == false) itemIterator = null while (itemIterator == null) { if (!iterator.hasNext()) { return false } else { val element = iterator.next() val nextItemIterator = iterator(transformer(element)) if (nextItemIterator.hasNext()) { itemIterator = nextItemIterator return true } } } return true } } }

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ITERATOR ࠗ࠙ SEQUENCE override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() var itemIterator: Iterator? = null override fun next(): E { if (!ensureItemIterator()) throw NoSuchElementException() return itemIterator!!.next() } override fun hasNext(): Boolean { return ensureItemIterator() } }

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ղࠗ ೣࣻ ࠗ࠙ SEQUENCE private fun ensureItemIterator(): Boolean { if (itemIterator?.hasNext() == false) itemIterator = null while (itemIterator == null) { if (!iterator.hasNext()) { return false } else { val element = iterator.next() val nextItemIterator = iterator(transformer(element)) if (nextItemIterator.hasNext()) { itemIterator = nextItemIterator return true } } } return true }

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׮द ITERATOR ࠗ࠙ SEQUENCE override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() var itemIterator: Iterator? = null override fun next(): E { if (!ensureItemIterator()) throw NoSuchElementException() return itemIterator!!.next() } override fun hasNext(): Boolean { return ensureItemIterator() } }

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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FILTER SEQUENCE fun Sequence.filter(predicate: (T) -> Boolean): Sequence { return FilteringSequence(this, true, predicate) }

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FILTER SEQUENCE fun Sequence.filter(predicate: (T) -> Boolean): Sequence { return FilteringSequence(this, true, predicate) }

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FILTER SEQUENCE internal class FilteringSequence(private val sequence: Sequence, private val sendWhen: Boolean = true, private val predicate: (T) -> Boolean ) : Sequence { override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() var nextState: Int = -1 // -1 for unknown, 0 for done, 1 for continue var nextItem: T? = null private fun calcNext() { while (iterator.hasNext()) { val item = iterator.next() if (predicate(item) == sendWhen) { nextItem = item nextState = 1 return } } nextState = 0 } override fun next(): T { if (nextState == -1) calcNext() if (nextState == 0) throw NoSuchElementException() val result = nextItem nextItem = null nextState = -1 @Suppress("UNCHECKED_CAST") return result as T } override fun hasNext(): Boolean { if (nextState == -1) calcNext() return nextState == 1 } } }

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ࢤࢿ੗ ࠗ࠙ SEQUENCE class FilteringSequence( private val sequence: Sequence, private val sendWhen: Boolean = true, private val predicate: (T) -> Boolean ) : Sequence

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ࢤࢿ੗ ࠗ࠙ SEQUENCE class FilteringSequence( private val sequence: Sequence, private val sendWhen: Boolean = true, private val predicate: (T) -> Boolean ) : Sequence

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ITERATOR ࠗ࠙ SEQUENCE override fun iterator(): Iterator = object : Iterator { val iterator = sequence.iterator() var nextState: Int = -1 // -1 for unknown, 0 for done, 1 for continue var nextItem: T? = null override fun next(): T { if (nextState == -1) calcNext() if (nextState == 0) throw NoSuchElementException() val result = nextItem nextItem = null nextState = -1 @Suppress("UNCHECKED_CAST") return result as T } override fun hasNext(): Boolean { if (nextState == -1) calcNext() return nextState == 1 } }

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NEXTSTATE, NEXTITEM? SEQUENCE nextState : calkNext() ೣࣻܳ ా೧ ೧׼ iteratorо unknown,done,continue઺ যڃ ࢚కੋ૑ܳ աఋմ׮.   (GenreateSequenceэ਷ ҃਋ initial unknown ۄח ࢚కч੉ ୶о੸ਵ۽ ઓ੤.) ex) GeneratorSequence, FilteringSequence, TakeWhileSequence nextItem : calkNext() ೣࣻܳ ా೧ ೧׼ iterator੄ ׮਺ Itemчਸ о૑ѱ غח ߸ࣻ. nextState, nextItem, calkNext()ח ࣁ౟۽ ઓ੤ೠ׮.

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ղࠗ ೣࣻ ࠗ࠙ SEQUENCE private fun calcNext() { while (iterator.hasNext()) { val item = iterator.next() if (predicate(item) == sendWhen) { nextItem = item nextState = 1 return } } nextState = 0 }

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ITERATOR ࠗ࠙ SEQUENCE override fun iterator(): Iterator = object : Iterator { override fun next(): T { if (nextState == -1) calcNext() if (nextState == 0) throw NoSuchElementException() val result = nextItem nextItem = null nextState = -1 @Suppress("UNCHECKED_CAST") return result as T } override fun hasNext(): Boolean { if (nextState == -1) calcNext() return nextState == 1 } }

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE (1..100).asSequence() .map { listOf(it) } .flatten() .filter { it % 3 == 0 } .forEach { println(it) }

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FOREACH SEQUENCE fun Sequence.forEach(action: (T) -> Unit): Unit { for (element in this) action(element) }

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਋ܻо ࢓ಝࠅ ௏٘! SEQUENCE fun Sequence.forEach(action: (T) -> Unit): Unit { for (element in this) action(element) } Terminate Sequence method

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੿ܻೞݶ! SEQUENCE Sequence੄ chaining਷ ૊п੸ਵ۽ ۽૒੉ ࣻ೯غח Ѫ੉ ইצ Terminate methodо ഐ୹ ؼ ٸ ೧׼ methodী ٮܲ Ѿҗ ч੉ ഐ୹غח lazy initializeߑध ੑפ׮. ٮۄࢲ ੘਷ ࢎ੉ૉܳ о૑Ҋ ੓ਸ ҃਋ listࠁ׮ ো࢑੉ ו۰૕ ࣻ ੓ਵա ୽࠙൤ ݆਷ ন੄ ࢎ੉ૉ ഑਷ ﬁnd, ﬁrstэ਷ ౠ੿ чਸ ߈ജ߉Ҋ रਸ ٸীח ؊ ബҗ੸ੌ ࣻ ੓णפ׮.

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OBSERVABLE

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OBSERVABLE੄ CHAINING਷.. OBSERVABLE п chain݃׮ ঌݏ਷ Observable৬ ؀਽ೞח Observer,Disposeableਸ ٜ݅য subscribeػ ٍ, ই੉మ੉ ߊ೯غݶ ୐ߣ૩ chainࠗఠ ݃૑݄ө૑ пп੄ Obsever۽૒੉ ࣻ೯غয Ѿҗޛ੉ ߈ജغח ߑध

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OBSERVABLE .ﬁlter() .map() Source(1..100) .subscribe() LamdaObserver MapObserver actual = LamdaObserver FilterObserver actual = MapObserver observer.onSubscribe() source.subscribe(observer) source.subscribe(observer) observer.onNext() ખ ؊ ੗ࣁ൤.. ObservableMap.subscribeActual(observer) ObservableFilter.subscribeActual(observer) Source.subscribeActual(observer)

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޷ܻ ঌই ل ࢎ೦ٜ OBSERVABLE ObjectHelper : ೧׼ ё୓о Nullੋ૑ ౸ױೞৈ Exceptionਸ thorw೧઱ח ৉ೡ੄ Helper RxJavaPlugins : RxJava Libraryীࢲ ݽٚ Streamী ؀ೞৈ ҕ ా੸ਵ۽ ୊ܻೞҊ र਷ ۽૒੉ ੓ਸٸ ࢎਊೞח Plugin ௥ೞѱ झఈೞѷणפ׮.

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௏٘о ցޖ ӡযਃ.. OBSERVABLE IDE۽ ૒੽ э੉ ࠁѷणפ׮!

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੿ܻೞݶ.. OBSERVABLE Observable੄ ই઱ ӝࠄ੸ੋ chainingߑध੉ যڌѱ ҳഅ غয੓ח૑݅ਸ ঌইࠄ Ѫ੉ӝ ٸޙী Hot stream, subject١ਸ पઁ۽ ࢎਊ೧ ࠁݴ ղࠗ ҳഅ ௏٘ܳ ੉೧೧ ࠁदחѦ ୶ୌ ೤פ׮ :)