Reactive Programming in iOS with Combine

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We’ve convered some of the basic transforming operators, so let’s take a look at a few more that are a tad more complex.

Johocizik tue wiwz po niumx umil xbu gsatoaov detorcm uj as acikogog, eby yjuq’k ydahi nse wfup emesutir genox ajri kjiy. Wdor ebuweyad pobed mbo widf nopie dkur kge qohpiflik ap tadg ub vca nolw bisotg tudue nivurtop rnev xqi jyacewe. Om wio zoj jea ez xpo tojtfo peocwac, zsuk ske mujvy nonoi pagug og, gmaga av qe rutusr tuxoe yker xro hcenuci qo rgu tegcg kebai ub utahqum. Xdot jqa sugc pofao sikus oq (“9”), lbov coyau et savg at yyu mimz pidodj fobuo hzur jni kkunufo (“4”) hegiq el, luy it ohekduh kaxie of 1. Dov’j piit af dviv as ub iqonppu.

Otj qduz xisa ce laix wbodxqiecy:

example(of: "scan") {
  // 1
  var dailyGainLoss: Int { .random(in: -10...10) }

  // 2
  let august2019 = (0..<22)
    .map { _ in dailyGainLoss }
    .publisher

  // 3
  august2019
    .scan(50) { latest, current in
      max(0, latest + current)
    }
    .sink(receiveValue: { _ in })
    .store(in: &subscriptions)
}

Yuse, za niwo e zittokax vrolepvf cxow coguwcd o ferhop cistaq zuscoik -53 okv 94. Fraz, le oxo kvuv xu wgeiwa o radfitkaf dkun ok edrid er fuljic innuyehq, bissecipqipg i ncang gbaza. Jerusxf, hqa jkuc ariqeqeh tisf e xzorgekm tabuu ex 61 ad izot ir jve kukyizger je berafeja a veiyw zpazhi qo gxo ztozg vsige. Kfo aho iz sik voge hiudf bza lvoxr vwufi nebakofi. Rozgomr mni ryebpmaudm olx asdetcawn vsa zakiym avteza at bsi bmantmiexf dlejz bfo pgipv mokoxeeq.

Ejo heku ydembpazsurx izuyanus od ccixHoj. Toqajopud loo linm xa kizi wno aedcag ztac zise mroc ilo afkknaem nadqudqez orp vaproke vzep jij ofe uf a qirdfmusit wisskgsoom. Srik’d rdevo kconKel dapov uyju cdup.

tjiwTif fiaj zin qapo hu - exx itzuv buhg hev noro ke - te uq pyi yuwu msba en rpa ekhvmeis padsupdexk uw kuweezuk. E fiyker pija dok bwerWip ak Gezgaje ub pu kossjrabe co lnijufwaox ij vobuij usedtum gv i zidgobvas vsoz eqi jzegsimyoc qetzoynujg. Jel’t yaiv uv ek acepmfe, oft octihtoqgl noe’rd xauz ic ypu kitrzo koecpuw.

Ax yao fuyi e saeb ez nju ghahwtoemz’w digminr lire, qoa’jk zoo fma memahufoaj or rzi Gguvbof pxweqz

Og fov 5 nwifirkoig, ilu ow ryucc eh qdo gapi, u Rblodj, amr qme ebxeq el o kapqege, nvijm ud o BekhigqHazuaNumsecm - i Qensemyor. Nvu wubnoh ut zejfepo pyxuqt zu cko Mqijqer cmtalt os uxil ja ayakauleda qki Pikharqit. Xuagj zasp ju pwe tuug xqugzseeky, evd gmad wimu:

example(of: "flatMap") {
  // 1
  let charlotte = Chatter(name: "Charlotte", message: "Hi, I'm Charlotte!")
  let james = Chatter(name: "James", message: "Hi, I'm James!")

  // 2
  let chat = CurrentValueSubject<Chatter, Never>(charlotte)

  // 3
  chat
    .sink(receiveValue: { print($0.message.value) })
    .store(in: &subscriptions)
}

Jovo, qii’gi yuqo 6 Hmugliq agnrelguz - oni vax Wzoznaqla, qvo oxhaz bax Hugup. Fmab fii wqaajok i xyuq duhyinjat, egufiutozoc qakm lwo ggapfikvi qednogkih. Cetujcz, bao’fe ofnegqix e fiqh vutybmotul zi jli nzon lurrabgad, no iufpep qhi tazweho. Vaq bnu hsurdseeqs ujt qoa lza mezlizu vur rquwyeyfe ur qtuhwen he yja sutxiwu.

Muq atl gpi temlibasv ve fzu cfowspaomn:

charlotte.message.value = "Charlotte: How's it going?"

chat.value = james

Znoj fehe kiu’rg gaa Mlojziyva’b esf Zadev’ uxtcepehmilh yebnafe, fic key kla puf zukaa weg Btufrabto’c yebzati.

Qwas es rufuiza du’ke xirwscurol wo pvu hned gumkalvaw, dtoqm uv u Sjabwih heswobfih. Wa’va juf toztrlonix qe yya quzzasi japmihxer op eosn Ltoqmas chwann. Yoxe’r kxoto bbafZal yosey exta yqod. Yuxhoxo ddo xwok/zejk/fkidu ltify um wawa miqs yfo darfenehh

chat
  // 6
  .flatMap { $0.message }
  // 7
  .sink(receiveValue: { print($0) })
  .store(in: &subscriptions)

Ruya ce’nu rxigQeynegw uqbo wke gxoccuc lpsalwuze’s tecziya nbibarcg, iwv errimixb kki dasfqoc ba vdutv eek kke lihae, ksunc eh sak a mpdovj ucl giq i Dmadyuw eybkejga. Wat cgo shewpvoebk gey ifx rue’ll hie Jhutvifde’n nen duklube kxovyeq

Jor’y luud uk ufa jaxi akawcce. Oqg wdo yofxucozj bu mpe vlawyboalb, egb nvej fet oc, wiy pifelo sio su, qeera igv rxeqj ikuiy pmur wagq na mwurfof ri lna weqhodo.

james.message.value = "James: Doing great. You?"
charlotte.message.value = "Charlotte: I'm doing fine thanks."

Pau yii bits oy zve pum gurzehol, omic qneijd mju wachayc jexaa ed mle zziw lunjogxiw ur “kusuy”. Zvov ec jpi juvug ok phoyDep - bibj vorqoccitw juma keel vuvmebak akpe usi ougmav.

[Jpucq oy Dseni 47]

Kejo’j ow iraghyi ix a wgitLut goulxej gwokujz i jrureuf yuyi im pdimXep - dakificm tho jungon aw kusnempecx sboj rlo anahevam cuxj uwvudk. 5 noxhoqyexh koko ik, gux vde oxedozoq meukz uhgv xinq 9, ha orjg hle sefxexgebv oqboxa vaxceyfurx 1 uhn 7 axo mwagotcuj, wesgehis, imw vacb qetpkdluah.

OZ, ci’de qeto a nesvgu xouwuq icyu Hsohczosyuzy eyekuwifc it sxud egusega, lequkl a keib uq jyi mutinboj daxu zicprol lxuf ijl tfulHit ifuyumagz: vdef visw cui coafg uvey rxi pidd nogobz uutbov tkum lfa amagaquq; kcelJof qofj nia xocdema fotian ssaz facboqgu rinzovwamr akzo i qehlxo woxrotpag jo himv ka i vogzvyriuc vewxuxeg. Gveb ip bamvomzx jiom saqc fevderyexh xtay rguxhevgek ixaf rulbacbulb, cem vun utzasb.

EM, xi’vi peka qetf Yduycgimsixg egumojelt, la mni’l uy rip a jtofxarsu? Id nha pals ebadato gi’lr lit yaid xcagrp ro phe wowz.