80 lines
1.9 KiB
Swift
80 lines
1.9 KiB
Swift
//: [<< Previous](@previous) - [Index](Index)
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import RxSwift
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/*:
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## Transforming Observables
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Operators that transform items that are emitted by an Observable.
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*/
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/*:
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### `map` / `select`
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Transform the items emitted by an Observable by applying a function to each item
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[More info in reactive.io website]( http://reactivex.io/documentation/operators/map.html )
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*/
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example("map") {
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let originalSequence = Observable.of(Character("A"), Character("B"), Character("C"))
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_ = originalSequence
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.map { char in
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char.hashValue
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}
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.subscribe { print($0) }
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}
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/*:
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### `flatMap`
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Transform the items emitted by an Observable into Observables, then flatten the emissions from those into a single Observable
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[More info in reactive.io website]( http://reactivex.io/documentation/operators/flatmap.html )
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*/
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example("flatMap") {
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let sequenceInt = Observable.of(1, 2, 3)
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let sequenceString = Observable.of("A", "B", "C", "D", "E", "F", "--")
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_ = sequenceInt
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.flatMap { (x:Int) -> Observable<String> in
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print("from sequenceInt \(x)")
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return sequenceString
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}
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.subscribe {
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print($0)
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}
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}
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/*:
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### `scan`
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Apply a function to each item emitted by an Observable, sequentially, and emit each successive value
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[More info in reactive.io website]( http://reactivex.io/documentation/operators/scan.html )
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*/
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example("scan") {
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let sequenceToSum = Observable.of(0, 1, 2, 3, 4, 5)
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_ = sequenceToSum
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.scan(0) { acum, elem in
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acum + elem
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}
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.subscribe {
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print($0)
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}
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}
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//: [Index](Index) - [Next >>](@next)
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