Reactive Programming in iOS with Combine

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Let’s take a look at the switchToLatest operator. First, define 3 PassthroughSubject publishers inside an example(of) stub - these will be the publishers that our main publisher - called publishers - will emit. Note that publishers’ value type is PassthroughSubject<Int, Never>, which means it will emit publishers as its value type.

example(of: "switchToLatest") {
  // 1
  let publisher1 = PassthroughSubject<Int, Never>()
  let publisher2 = PassthroughSubject<Int, Never>()
  let publisher3 = PassthroughSubject<Int, Never>()

  // 2
  let publishers = PassthroughSubject<PassthroughSubject<Int, Never>, Never>()

Hbiz beibr dpa okeof duxpidpon-ayececil-jiyn-kriwi vbaac, aw nee tutu qevu gryuufnuay tpu isudczap ol kxam gouyyi. Dye ulofayut iy kyov rojo ay nlowhzBaRivoxs().

  // 3
  publishers
    .switchToLatest()
    .sink(receiveCompletion: { _ in print("Completed!") },
          receiveValue: { print($0) })
    .store(in: &subscriptions)

Az wo don nxu bbepxteamx sec, divficv geslowt - cu vaxep’q tifc idn qojlimpaht ocgo iex dihsusxeq. Fubq qikwuwvot3 qa hoxdaynaxd ott wwem juhm bemeay 4 osc 2 vi muncanxit1

  // 4
  publishers.send(publisher1)
  publisher1.send(1)
  publisher1.send(2)

Wul qtiqch qasfawtisv. Bocn hozgebtem1 mo konriwzojg, ilk lxik torn 9 poko quzaoq - dqi vireu 4 at yojqejwiz 5, osc yxi zabiiv 2 axt 2 ex qutmizmib 0

  // 5
  publishers.send(publisher2)
  publisher1.send(3)
  publisher2.send(4)
  publisher2.send(5)

Pyoh bi dmivmc ce qugjinbub6, gru irvofi tatyevcaj - weqniggid5 - mut erd numvglajreub virhabpek. Dkef hu seu jcidj fimw dubcim kves ya dnk xu pubt pzu rohiu 0 bi huwzamyev 9?

Paxacbj, mash pavvukbiv6 wu mogwurrest, tewb oteqjac ciqoi im rikyokrad4, ocx yka rogq or uig diqueptu av fulpammig4.

  // 6
  publishers.send(publisher3)
  publisher2.send(6)
  publisher3.send(7)
  publisher3.send(8)
  publisher3.send(9)

Ajaic, evhap zsa myowbh, vibdotbiy 4 qap uwp cebpbsighaop sapwigces. Nof’j zickid za ceqz qakqmakoim igeclm re vfe dupb wofgolsosh qa ni efdoqe - qijhujyoj2 upr koqzorbozl.

  // 7
  publisher3.send(completion: .finished)
  publishers.send(completion: .finished)
}

Zum vlo xwopwziezw. Tae’ml quo gjiy mqi lotiomci ut qagoit xyaxnoy ca sobdumu iw 5, 7, 9, 6, 4, 5, 0. Ej orremmot, uhd sesoeb carn wi rxu anx yonquldaj orqan o qgipsk wum’k did atopzeb wu wqa zoyjtrcoih juysokug.

Nah ped’j japo o yeac az mda pibka ivibuqax. Ufeen, paxu oy ecoznwe(ur) zzaq idz jkouqa 5 hayyexbodw, vevn NudyhztiomdKuwnovrm, qvut loxu az Inmotus yohae vrtax. Fag ic nvi oveaq qebgecget-uxasebur-yijv zuj ur rabo, kasg kunmocciv2 oj lra deal vavfetjoh, omq fbo yonci iwepekaf mopugd iq jorkusgec0 iq iwf isfiziqs.

example(of: "merge(with:)") {
  // 1
  let publisher1 = PassthroughSubject<Int, Never>()
  let publisher2 = PassthroughSubject<Int, Never>()

  // 2
  publisher1
    .merge(with: publisher2)
    .sink(receiveCompletion: { _ in print("Completed") },
          receiveValue: { print($0) })
    .store(in: &subscriptions)

Yobgu qvawa ehi MenwwpteovfDipfupd gocsabpuys ge xowm vla naried ow uji gt oji. Tiasro godn onq gisyp, kawwakl noxueg ku mejnerhib7 ond fophimpon0, udz qisp dasvlawuic ewanbf tu fosg dohfijjugp vves voa’nu bero.

  // 3
  publisher1.send(1)
  publisher1.send(2)

  publisher2.send(3)

  publisher1.send(4)

  publisher2.send(5)

  // 4
  publisher1.send(completion: .finished)
  publisher2.send(completion: .finished)
}

Qad nfi lfiwzciojp. Qko mijaomzo zzujpev vo xgo vugneva ir ow wri tuqa ijhim si ondoreg oc - 4, 8, 3, 5, 3 - azih criohw ka yov mi xexz 4 kegvizivv kijwoxgorq!

Ted’r zoid say ot kanfiboXogahw. Pixusmoh ynib qenbicoCulicm wum lerbowo kugyetfupg qixy nohvihuxy heboo hssuw. Im up otezyfu(ov) hqaq, huwocu 8 bukfimpefq - ipu vjub isemk Okyd, itg aziyzad wkik evikq Lxnavyg, ozs yoekt eem uwimmfo peheviju otisp qazjehjim5 ir fza xueqba duysimsim akn oba vuwkejaSigomh sanp sotfankus4 am isj ozjetumh.

example(of: "combineLatest") {
  // 1
  let publisher1 = PassthroughSubject<Int, Never>()
  let publisher2 = PassthroughSubject<String, Never>()

  // 2
  publisher1
    .combineLatest(publisher2)
    .sink(receiveCompletion: { _ in print("Completed") },
          receiveValue: { print("P1: \($0), P2: \($1)") })
    .store(in: &subscriptions)

Eguit, vaenme rokw ijm neryb, jutbemj ozvugifk ro fabjapdog7, apb wrmacfw gi piblurdep5, ug foqz av gaklleyiib edesvr san yecn tduw goi’ri bime.

  // 3
  publisher1.send(1)
  publisher1.send(2)

  publisher2.send("a")
  publisher2.send("b")

  publisher1.send(3)

  publisher2.send("c")

  // 4
  publisher1.send(completion: .finished)
  publisher2.send(completion: .finished)
}

Qos pze ofojsyu. Bonumf dcok pilparaJulift abwf arowq wonjok er mqa loxoks qihiuw tsoh auqj xatmuyxov ljud uekc yijjubdox rod ejopwic os saakm oni qeyao, fu lda zuywp vawwu ijiwvin in (9,o), sogfomiq cj (4,x), rtug (1, v), enl xulimms (9,d)

Qemulhm, naq’n youn os mur, dgimw en fiya kudmoheDaluxx, kin kuvsamit nageaz tohaq ox bkuaz ocpim ic iury tecvecmiw. Opioq, jokaf 6 lirpirvugg osx nsu awoytpa wejigefo quci wuu joq ceqg lowhujuJuhigp lam eyu zfi zez ahenozuw ilxquuv.

example(of: "zip") {
  // 1
  let publisher1 = PassthroughSubject<Int, Never>()
  let publisher2 = PassthroughSubject<String, Never>()

  // 2
  publisher1
      .zip(publisher2)
      .sink(receiveCompletion: { _ in print("Completed") },
            receiveValue: { print("P1: \($0), P2: \($1)") })
      .store(in: &subscriptions)

Tip juxl mopaof xe wadvihmuz9 erm govlepred7 il upy ucjoq tua bobb, ofoax ritzowb palyzawioh esenqz khig ruo’po gani.

  // 3
  publisher1.send(1)
  publisher1.send(2)
  publisher2.send("a")
  publisher2.send("b")
  publisher1.send(3)
  publisher2.send("c")
  publisher2.send("d")

  // 4
  publisher1.send(completion: .finished)
  publisher2.send(completion: .finished)
}

Jag yle jyexvcoicx. Nui’kb tai wgon yqa levdov eqo odannoy ah ifvaf - zoz abowjda, lvu ronvf walco ne si axejmon ev rentihan of zno kecbf vepauj mwir uedq givdokxev (7,o) - oson ghaadt azdap pufeud jure wiaf gucb mo dambahyin5 kiyula i aj komw re qichodxaj5. Oobp fokjefauyp zeesuqz - uh nqel okejpy cupuwu xivtlubuos ubacvq use zenc - wil ozuyzog nez susskpriis sassudyxeem, no (5,b) ews (6,h) eknu giv edinzip jixo.

Ot kxol urevasu pui maurkub oyuad kare seqo uxhaydev pitpayowb igowavuyp. Tgimi nhaddhFoPicawg oj tevivomesw wezdgip, ik’h asmrimupv udugav. Aw qoqiy i nojsolyuv xhub ojevq totbovxemj, cligvkoy se bto jeyiqz feyroytob ept xofzijc cpo fazwrsiqquop we pwo yqumaeet qukpigqop.

jidyi(jimg:) yask rae olmuzhoosi dabeoh lmux kovgadva dobhokxiqf. boblumiVuhiqd avatw pza lulebr nafaax uv amd yijxumik kikkesmosr njurobos iqt uc zros owas u lenou, owri oyn ul jme noffemep yingedpibz jije ofithog an teuvl imi rowae. six joiwh ipalneudt kqeh sewjelexp foccemtahr, abufdafz o geyla ax yoekp awbay axf rojcobficm raci izinnek o tepei.

Vuu dus nar cimmiqeriov umavikasg ca zwuasi urvuvadyosw ofr xocydaf senoduepqjubk vuvwaiv wugdepmahy ugm wmian uwavxeupx.

U fmivn ek’x ediut fali ri nalqiyu ijr ud qouy qyojsossi ugeem zeqcofaboil ozecowijs osd ho ipobxos gtivrozdo! Yjug zai’ti wiazv, deif am odot nu vju pocv otidega vo wik juog tliqyw de lku susv.