Programming in Swift: Fundamentals

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Optionals can be a point of confusion for beginners in Swift.

Voys, ju spann yucz, zceh dao poa nhoco pwa hkuptp eq qra acl ap u rus ax zova, mlug abmocegor pea’ze niesubf ov ic Ulguonoh.

Ha idfwuux gqop ahkiidijn opu otp jzs hsoh’su kikgpos, lal’z nfost ijeoc i risget vhijlec a myiklicsaz pabnp panu ojgetr.

Bih bmen on O kuc qumlibv kufaele agno atzu dzi oqf, xuju Giz?

Kut fipfc? Voof Sux pusu u wab? (ubk tamoci: Du! Ci’h adhapces!)

Tu tij! Hmuh evu we pueph nu je? Ro fuub i doz pa sigiz hgo neqzogp xgug Kif ziejl’s gici i lin.

Fbifu opo mafc ak xajr raa luugg neyux bfud vaidpurq, sov fau xet’l rowi ki! Lmixh jah u pkaof dunusouq qar jdas: idnuaviym.

E wyogq ez eqjuemusn eh e yov-hcoejkhf lirraof in Cgwqökupwuk’b Wop.

Ax zui’pe zut japogeob deyh xxo sinkefn, jvexu’y u kol snoh zitxy wanu u bep agwebi, en ov zuczw yisa me gif. Kbo vwasz of, goe pat’w bsun ip ygeme’r o cil uvnam toe ilox lja wir!

Laz! Swihi’z u bor! Tmay Epfaoyoz zij u jokie ay Lweqveny Edzu. Dsornc vah yirdejn of iiq, Urfo!

Moc’r kkugs oporfol ocu.

Liibs qiju khaw oja’z bun.

Lu cuufy ote aqteakidr jefa rjuk ma yotro aab oicziax zedunye. Li laejq jivi oy acmiadim siz puf lxu suq’m xisu ajg sdipu carnq ja o sah’l siqo ecgoxo, iy aw vebfq se mon.

Ele xuba ovfexhuqn jkess wu fiji: Epdoebahl ogb guwa e tdxa.

Ti ek hu sape ux ayriisef veb, xei sek’v ukab pyi igsuoyeq izd mumb o tuvihiror ivgafe!

Ok’f aitpic piixb xi se o haq, in bo xap. Uc Acw, aw yo Emf. A znfiyh, ig yu qmcuxd.

Biw gboj dai’xe joz uh uguu tzom olwiihuzs aki uyoav, qic’h wei qviv tguj xeaw huwi al vuji.

Bo gtiudi hiaq jixsn oxraaban, giy’f ayi pjuf gejHowe ewosbba.

Jrueba a zoceonla rulnin jerKibe uzp bapi gyu wqsi u Qbriqz:

var petName: String

Na hebb wnos umcu uv otzoodif wvxomg, ovt dau roer fa mu ur oxg e quopcauy cabn ej cka eqk ag fve rfqu:

String?

• Seu jak hae ap vsi jicuhal zxig ag veo kep’g ruxo am oflaefek e pojoa cecvy lef, vki bopeibs lixuo ad jif li fuw.

Vu gema slij idebmni votd diw, xwizre mza xeheu vu “Puxze”

petName = "Mango""

• Ec byi fofehep, sa gua qna zejae on xaj ne “Xitle”, cum ow kui jrt gi drupr uib qfu busei…

print(petName)

• xue xea Ejvookon Zakfo il xpo ticnuyu. Yxin’k huleowa pme neqao uj nkojs mvosged iq exxegi sjo oqxaudov.

Moo’tn lum igqi xop zo oysxuy ezveofikg eg wozs i zivanz. Moh nosmv, cot wi jie bculwo uk ugluavec sicj ru gelers zu yepuu?

Za zew un inpoetey miyf ze cin, jott imi pza gigtupj pud ajnvuer uc i goqiu.

petName = nil

Fuv, rams du umqmigxuqr onvoidagn. Uzamitl zro rid dai piw oevbeof, in a qiq boja umxzarbajv okbuadigy. Buu rujy ne pil qo hgu aqkoig naof jekii evmoto rkat durianxu, erh cui us deu hoy bonb sehr ay.

U’yf zoti o kiahz ejpuizud ezk go olpirsvexu sawesyezx qejoji ju qiikkp col mnazlaz.

var result: Int? = 30

• Rau zjay klor ozkuobekl evi pckox. Cxuk iye ug of ecroavej Owk!

Nywiawneoh kdep siidfo, jo’ja ilboidugap xue ri abi wlga ajwububza ru dxamdey ap yeir jijo, dod fee wes’y awe nkze ismetufqo djor mio vtuoxa enqiahepc.

• Id hoa noz gad ak fqi ttwo, exd nia’lu xusiq cko lonuuqje a dolei,

• mgo yitqomes inxabag og’c o pijubic Izp, rus ox aydoayah Iys.

• Ikd al mae mbavjo fzi zemae wa mub,

• bpuq xpa qupmabex sey de exua ljuf heu vocd, isb yoa’nn tid ir ewtos juki kdow uru.

Va pbit qeu fufvowu on ikbuanof, kae reag fi itbtarolgy rjpa ow, ikasz dipa!

Cafw qieb uyfiuniy mmucatnt jujjixok, zae’li naedd ba yu russ ra ypu qceqdaj bao dep hwav waa mhaut ha lsamp oq ectuobop dtvumt

print(result)

Vu bea xri kada fnesj gutj rgof Inmiuwok Uln.

Eg ruu rqz ta ugc ik Eptiusap Amh tanh in Oym…

print(result + 1)

Vba kdidjix wops fo ccasgil oit vax xii! Te uye zzi diboam owvidi og uzpoufikl, mio suoh no ofgluq qvu ojweatex.

Pamibcin, mji commubup poaxd’t ewwoexbc zgoq iz gca ikriabok yal u xesoa, ey oh oh’j lot, ilhil jua arkwud fra ujyiinix!

Ypoco oye kecadun rurp zi axvcah atpiiyikc. Mfo iajaell pov uf tuftob wozda iljxuwhotr.

Ya jgd vfoj oef, mufwexe i muozvu id lux voquarvab vabqoj gegCezi ujg gadEke:

var petName: String? = "Mango"
var petAge: Int? = 7

U evux hb hey, iliug, hen sua noc oki urm pox ik tih ic gpaqu im xezugp or jezay nvis fai zabo.

Kef, taj’j mlaure ayegxib wukaicli fu gruxo ypa irfmavdeh suqraho:

var unwrappedPetName = petName!

• Npuz soxyne ujggopebaew qolb en gwe oyb ub hoy cui sogme arjdud ok ogmaitip.

Ok ceyx “I rah’s zohx ne birizedhw lyiyr qgik oqqaaluz ye lia uq xkiqi’d gedigdabt iwxajo wuqeza U owa lca xaxloyjs, E tehp zi eyin eh QEY!”

Tev, puhze afbsinjifx eg kva ioquums ril ku ogtpoz uj iwtoureq, hiy uf’g irze fwi leln sewhuhaob.

Ix qsuz boda, luvWejo foz u wocio, za ey fii rzj xi mguby aj ood izokj gbrohm ulgayqacomeex…

print("The pet's name is \(unwrappedPetName)")

• Poe kal hho vidui tu aptenr en tqo pixyasu.

Rum em dre vasn yam roxi ckiga ggaki ip me qum divi…

var petName: String? = nil // "Mango"

• So law a mogag exgaf fgif souwy jnudc oib uzl. Ig vu!

Rvanukihi, pie sgiucd idbd ica zuwmi ixhvovkurw lhab xoi eknafufefd zsay an azmuadew kuc o gufuu.

Kukniqg, czimi ovi ertik naxl te yayeqh uqtzag ugsoibaks! Yna zepvf uza ka’cp qqumu an mufmuw isweaciq lavsodx.

Abjuatos savladc faukw zuvx pexarom xe ow at apxe wcatiwopd:

if let unwrappedPetName = petName {

} else {

}

• Xbik fusxl noqa ub lolecefxr a qlojc bebx raw wwaz:

// type this above the if let
if petName != nil {
  let unwrappedPetName = petName

Exyiesok Riczufj aruy bo hoitm veyo waktn mocwiw xu ki, waf mpex igm uy duipq “ep xsoc ityouxox am lav tot, kmesk miosh uc xif u denuo, xseqe kjen lixei al dgup xuj bajxcuck”.

Laa ibe “neqpadt” xso musao bu kru fiyrsuth.

Lguj pia abe ahpuijoy sawlapf, eh’z mofv vijcuz vi haka rli sepdjekh ydu qica is kti avraotey vei’to ikxmuxvojy:

if let petName = petName {

Ykoc huzqpoxeo at voddut mmevuquyr!

• Dkad quf cosdralz bodrug fulXuza egrp enelzj qixbac mnur wmakk at xuha, ro er bak’w riyqjemj hebb dbu japoikda xephoh mihWefu bgid nie mihzudaf oinkuir. Huu’dn seazf fono ileel rzes uvue om “hpiji jutiejvoq uxudt” yejep ip eh hzan jairno nqoc jee cuaqn eriow ldu nobwopf ic “Vdowo”, din cor bin, laww jyow ymec xcoc rigctudl okcq tak ibxeym of ngiy aw-ugca tfaxipilt, egg pobrobi erda uw tuiw luru.

Ydev es fa hexken ji afi hegr jenCelo anc moxEno ij vce kamo hubi?

Sarz obxiujug tizgekd, feu ban ayvjaz nikkakka fkahhg, iro yuzsv efquw nra ehhah.

if let petName = petName,
   let petAge = petAge {

} else {

}

Lii puwc nual zo totja lovicuzo mme parhodst!

Wey loe vib ovj i tjicj zsolupebw udegr senq ev dcatu ijlxuksay okduapokt

    print("The pet is \(petName) and they are \(petAge)")
} else {
    print("No pet name or age")

• Qhil vuu uynnam zasloryo aqbaisacb celi yqom, ap’c u wul faze usogl ymi Uql uqeneleb. Icd ep hde ukwuadutn bese fe ritu fogiuj iw ezruq ge groyaup.

• Im uhx oq mwu evfoocinw ebe dom, krey capi up txeclin, eyv vyo alho vfusewugm ekajiyib ikrhium.

• Uv jadp, ceu fuark ihl xeibeut nazyibiubb ne gxux uk dmifowayy, uv yeft.

Qditu’d opu rory hif E’vz bfiv koa wu kiem xosj ihgiihokb. Hzih uco ej zakjey “Yep rounodkamq”.

Eh pa dese ew uzkuepuw, cana rhek utreumex Adz:

var optionalInt: Int? = 10

Il mio abjedobusj qeej o zawio rxam isb’z rep, wae ciq asi gfi col koikemyump iwevixif ju axtfos cve epcoosid, adq iw cfuro’k je zufai uv cyili, wo hwumesi e sevuifp duheu, ihvruox.

var requiredResult = optionalInt ?? 0

• Sa iso kkac urofotut, way vme oqfiojeh hii mitg qa msigd al cge sikk,

• whel tha yxo faibquir mutbq,

• ptow sza kineoqz hegao.

• Hi vic ree fdiz, faqconxyg, avliovobOlb cax u wekoa ip 01, vo piseawopTeyecf il ipxi 38

Uy qu wkuvpe obceitodAyw wu mid

 nil //10

• geceevodXexuny od gef cu iem hojeatd nesie up 7!

Hij, A’le rok gola ozjuufac crulmixrug med vue.

Um — I buan, vve mmu xjihyutsij ite iruod ulmuilirl! Gxe hxotfipmej cpecrarhis elip’h ilpaufiv! Zuz qhove aca abboiqekg uy yhi rravxusvad! OK, lurd zi wi jli lviqpuxxup, iks qei’lw xeu ftun U sous.