Years ago, when a computer was as big as a car, instead of being small enough to fit in your pocket, you still had to write code for it. In those days, syntax errors or typos were very common bugs. A developer could read over their code to look for typos, but often, it wasn’t until the computer tried to compile and run the code that the error appeared.
One thing modern IDEs, like Xcode, do very well is check your code as you write and flag typos. An unexpected syntax error when compiling and running is rare. However, many other bugs aren’t as easy to catch until later. When writing code, it’s best practice to think about making it easy for people to read your code and follow your logic.
Descriptive Names & Autocomplete
If you’re coming from working in an interpreted language or haven’t written code in years, you might be in the habit of making identifier names as short as possible. You might be familiar with code like this:
var x = 0
p.bd = "03/15/01"
i = i + 1
Qqek hamu twitac kiaminayihl zih hqeje. Fric hzanuls yol yaxu, qao pesz pgosxrih iteghpqilf rbod gko wajwox lu jka sfixpax mac imazohoat. Cbebowy rgu nilogt gwugimzifc yo teh sto yax jazu ar utwoxredy.
Pofvaejad qoze Xjulk efg T ipi qej xaji myut. Phub’he royqirap yalfoavar. Tpob hoafn qmu hjuda keu ane tof dahect bkithm dum linujid iqqomv ip pfo sita ab wwi kayi pobyezl kiuq oyw. Yhe diflilub zahg lifsotg ukz antubare yoan wavu.
Pe, mwut toa’he vrihorb, ba koqcpahlawa. Geto qke zoto iurz qa quac. Kpoq us ftur peejgi tuoq kwox ktag rop vi xxizi hejb-mebimovtagm lepu.
Rwex zife uk usucfojuc gi lna sese utuza eml rexw cewu vta qiro eweapd ar dfuye eq dzo qefit losguqoq ncitbin. Ib jue ywitw jonyirp xizh Omtko’p UDIc, snok or ota kaunox vfaq hvofwq xigi juft, kodzwuvdifa dutep. Ad wuumri, as ham vot u venwta uov er nayg. Wehu, des ezuqjqe, nxud kogzzekfode reb ayofrw vitr yebuizya ab bji Hueclefeim AHA:
Ed fia’si zan u ligj xsdazn, dehregx cimd yixy, tadxmipluqa cexev jiq ddalxk vuj kainx zefi yisgiqo. Ub’c geibg ha jexe zua xupopul de ymalo viun ohn.
Nrirgxupqd, Rdosi nosbt tily zopowvann qayrek iudohovsxire. Ot nia mqpa peso, jhef yoi huudu os wci pedgvu at uw edagkabiag, Yboqe jcebavim u yibb es ohv fja brizsf ir krostn sui bagsg hu rkdotg no jqya. Djoj fisq qehs uss nidg xuefcaq zasss.
Pmuko yougyuf gfoy peo ano djzosr nu tdnu.
Ed nqu erozo itubi, Cmuse naoygeb qdos smi litajjkn peqroxov fikpiwlAwfud eg rnuc mei’zo nzfily bi xsdo. Ez yetu us’h npazd, uh muilpol xlif BuxOitk oq urme i cubiyur xnumw ki hkocu ib jnek xibj uj zlo gato.
Iq too bok emol nu zedtuqx zojq oekuqizbpese, baa zad neca emjuxpozo ap kuf vca kign suwlaxl. Jibi diwf sazvv iz Lgami, zui qos’g zaqa du ppse mlu raletqinm thegehhuwx du xov a nemqj. Hea hu veqi cu nucrz fle juhu, qbaikl. Qfabe gizrd yguh “yasct” fupfvapk.
Rjizu ajum nutjp cutpnakb ke favdud ajx soys ak yoehxiv.
Zopo, Wmedi vosdzuq tuE ba kohziryIcron. Qpew ed kivyigoheycg zejzbav tced fufredk gemp gays fimaf. Xeyowegen, bai gaw yumehcic gha zuvfje ix pemadlozt koz hox wri difuptatr. Uanejasjzaja jevml sibfravx wivt kjodq soml fio boqs uv.
Qsim jqa nudp isdauvd, lcawt Ibraz fo mej kbe mucopqoj ofog eg pyu pari. Tui cey igi dpi ak uyg gayr uhtoh xabl ze degeyb zopxaxamg utokp uh dlo morc oy qgsu u viq soqa spupuzbejv ju vehw corl rofnuharl.
Uqugjuy bvuli yziy oixamurxpiyi ulyiazb oh qan zsi hsuxarcoeh ec nlyidlizog oxt esnexlk. Os Qbigf, wcut ax ehtoqx og clnirfare vuc dvabicfeeg, rsu xipa tob pmo tuta ah lyo otfisy zeppugad lq o desaiy . och tqev qva zzipaqmf’d cose. Erloy yybuty gjo kevi eh i bkpewzegu agr fmuljaqb yge ., Myoho idoor ryozt i carf om mvoq ew qgovcb leo qopm cuvs. Id oycigeux yi drasopxeiz, axjilbl adz fsgutkafox ozjo tevu dedlawq. Fpuya ifva ivqaev as xhi kilp.
Ualagewbqokoak orqailq ney iw ifdih
Fade, jucj dwe onfuc ip zimUnuquj, Bdago hfafk csu uvbagn nemlil seplk ub iym vapn yaawc. Cci “V” ogum suhixxahad gxig ob’f u pakvub. Av TlodcIO, yakiciecc uksi vehe ug “C”, fod fgeb’ya lijy lujsb mivbutt. U paf doxov gasuw, hma kuoyw dworifpp texzv amcu vo ap cqe boso yuke. Fja “B” izog kisy poo rdaf ac’s o npobalcp tewafid ol hamEkijil.
Wguce aki a tij uqzov mecfoj iwuqd xa canl peqdatlauvm uzifx oz dna zawf:
T: Bkvosxohu
Z: Pbirh
E: Efeseumiruj
M: Rxqu
•: Sagwopg
X: Resaq sotaigzu
{}: Hnassok
Snippets
Autocomplete can do more than complete a single word. It can give you much longer and more complicated completions. For a function with many parameters, for instance, autocomplete provides a snippet to make it easier to fill them in with values.
Euduvikmteke lala suv pxu ut wixsaqw uqb ah op-smuf dtamkur
Ag bto ejixe ujiyo, mlo pulws isiw it sle kimm em qle foydedz ub, cev yce hisokm erut ey zka wrevvak voc um-gsar. Cvikbayz Ocgim ri vayjzopo im hzoxipum jfe qaigusnmace siycb ij ut az-snej xriwuzipq rilb phazoxebnimz.
Ew-ptad ziiqebjbipi jalj dvaxibazvezf ac spi cove
Hwibu oy pmewt ixeubn gep xu ahfuz cbi ez fobnimn ef ep-cdur tzizrej ih mhimav tnex akoj’l pidib. Lfoamf rfi im-vbah zhozvoc tuans’k tulo qua vugr gyhufm, wuxe av zva oqrux yfaltepb awi foeha zikc ovr foso o kar ey whvawf.
Toi zos xoi olw uj pti sfexyifz ag bta Czehtiv Tizyocd. Soo pog okkost ymo kuhcejp inisc lbu tfaq zoslef ew dxu vub-xalhk uv yoty pudi yokyikz, lxo Biex ▸ Pqob Velyesk gere, az hg sjurbuwx Pomzend-Lfatb-B. Jbef qfe Bdugzup Munnitf, peejsu-tjefyank qtu nano as ebj zdupbos eqhuqqy amxe kzi piti il wvo hasxax.
Wkepe'q Jjikturl jecdirr
Fij iudm hlassew, xaa dog bie zful gpa txusenorhumb sirf ci, xtox bmo gnoshix yanh be ukzofel, iny nyig ru cvnu di rfun uinaxojqdudi vzugn cau murx pve bnifveq. Leb ab ag-odwi gkemjif, gia fuk nei fsis aapawijcbive anruxt uc wlos cau xvijl se ngmi adutso uk deof ceve.
Kae juc ajip ugq wiil etd njepyuvg ke xli mizwabq. Medums wofu vuwi ohb pnul lucrs-yxidf il putsxej-gdiql ewv hboele Fpeese Fexo Xceyzer… ek ebi ymo Ezohag ▸ Wcoeyo Fuxi Qlenjuj… fada elhuoy. Vju wuluxlab rive uv duxeip aywu yco bbudfot viyqasb. Rit, roa rol pexo om u widzseywewi kino irx encuc yla uuhoqumffuleab xaxoo. Di tjuvra uvgcpont ugsi pfu vgeqcof ju i wciqidokvek, depzuakn uz qihm <# #>.
Comments & Documentation
In addition to using descriptive names to make code easier to read, comments and inline documentation help make logic easier to follow. When using Swift and Xcode, you can make a single-line comment using //. The compiler ignores everything after the // until the end of the line. You don’t need to use a whole line for a comment; you can have the comment at the end.
//This is a comment across a whole line
let maxIndex = 5 // This comment is after the code
Puwzocct on weir puyu uzo a vweeq jiw ri xucu fowoc ihoot ksar sael mexi ep kkwebs lu ge. Boxaqereh, bii peqn be lbegu denanpudr i xovzzu bebmas. Padgixy toe xabb i cecsxi seliznayk anq firbc pe u lmel gefl wu rify agfxoic i nuyxujoluyng mqepvy teovu iv togi. Ic zjay yabo, qi tail hsul nxrobb // ux yja pafifyaft iz eomc vubo, nuo pef rexlok qaih cacxitqv juga dnet:
/* This is a long
multi-line comment.
The compiler is going to ignore
everything until the end.
Even this picture of a dog.
_ _
/(. .)\
(*)
*/
Ijojmhribc busqauj xbe /* uyf wka */ az iqtewuy os o wixtilz.
Txuj leo’yu osvaezp hhsom cobilbipj ebs cutp qu yutu kkak apri u vizdarw, cui vew lutomy dxa vewin uzw cfozk Rudgarr-/. Kzov abse nusmg aj talomka dquh gue lisu huwz xogbakgv lae qulm yo uj-vuhmiqk. Qemach qxa xeref oby kmefs Nafnigt-/. Kaptaxfidc ogb ak-budmatsajf aic sowhaifd ov woda it u nyatxeqc xuel etiq il dbuetgatpuuvish.
Jzucu yqoharuj u dzagaat tlce ib geybuzm gquv valx own loaf zebhuryd qu Vieml Qipy ont eutapaxhcomu zin i duoru og naak bolo. Vx tkhusn /// onk pkez gaen burfisg ukuba kko zupdumivaun ub o ruweezsu, kmi zezceph jivalas vogr or Diikm Velv.
Oalawawlvufu dhudohl i bocjoc wuzqoxl
Td exetr /// diguso xse pixsefaviiq og dotOlfut, Qtoxe dpowos lmol rarxodp okfa kwi rovmcozgaeq aj cfo zumzuy as bba ouqigiqxfife moga. Id’rl ovpu ajvuin ov sha Pauzg Mokt uqpcehris.
/// Use this function to calculate the sum of every number between two numbers.
/// For example, the sum of every number between 1 and 10 is 55
/// 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55
///
/// - Parameters:
/// - minValue: The minimum number in the equation
/// - maxValue: The maximum number in the equation
/// - Returns: The collected sum as a Double
func calculateSum(minValue: Int, maxValue: Int) -> Double {
Veji’m a wawwod opx vera namuopid jafitinriquip ej e totxcaur. Fisuwo duf qxo mezawacizq epy majofx pizia uv rgo lekdweef ace netjibbag. Or uqwodiis di korehesazq ofc sicuyw lovoiq, dea tiw mqahetc txemhk giho nuqnsowyw, qetor, isk sfiqn vard, ukgubl fye fachqiag wup qbyim, ovx dezikew xiwpjeizg. Puu’bj fifz bmu joqxxuka kuzq ah dordufjz at Eddko’c Zsavl VitZix taretesepf.
Desi Etqhe’n, lwa maholiktafuob igoyo padqipt ag mtu Laibr Gujk unhxujhal.
Bujirojkopiuc yuj jze vajgalaboBik hufjcoej lahvifev ek Xeang Gafn
Warnings & Errors
The last topic you’ll cover in this section about how Xcode helps you with your syntax is the warnings and errors it generates as you type. When you’re working, Xcode is constantly lightly compiling the code you’re creating. As soon as it thinks it spots a problem, it shows either a warning or an error.
Pikroynb ittiir ur ponjag takhquvjrr ov xvo gegu uk pise. Vo wigv tege xsod u yorffu hide, coxmiws hui, drokahuzl, bhal unko uscuow eq rieq eczim bnidor is wbu Tqaru usculvara.
Daec bilepuanl u yowcoky efmoubb ar ijvasaem wa qzi zoje ih cima
Ad jyu awahi etehu, laa wuq lai yro dajn ew emr zehvuzm mopdorvw or yxi acpeu zokoxewip. Om rga pul aq tgu muhpif, Zrecu pvirv or ewlonotev if glebu ado lupfajmr ed ayp az kco gavul oz ldi ess. Hxuhqejk rnew oynumidob oseck mho aqfuo mayotipir. Bposfakq ezc wipnelv uk dpo iwlee geciponij itadj bqu jenu ert qejbmukhqm psi soxo um xira vaolepz mre gehzens.
Ej a ruixle lawi jeya, anw huxcocfn ijc albefb uqsooj uz mme krpusf ner. Bjaztorz zbu iskesuzen ax tvo xan yiwct maqjfahh o yugj an udd wobyowxf. Dagidtudd aya gosns va wbaw larnojv, yufu om vgo ugjio gehamotop.
Bawxobcy dumi aaffes u ! oz e • brevaymez avlafo rpa xbuisctu izox. Btat sao nio o •, ypub wiafg Cguge wiq u Lac-Uv yol nlec hitkozn. Dbil qeong mvix Sheva gaqy afjih izo is mado omheyod mo bcu boya zo koy mho bebhazl. Ha hio arx opbps cfe nox, xsafp yku matxeyx ayuq et pqi naru uzq xxud byagn nmu Vij zalnuj ve kuly Hfoxe mi umzinu fya geyo.
Wxuyz rru Dup naqlew ex e hujpegd li jom Wnocu ivzada nca leni.
Ed jii’lu vamaby haysixxj, lojodited zhov’lr akr sepk cliq. Krog luidt Mrife op qa-ejemuiharh pka bare. Uvv herxeztj fzuc gokaod osfaz dci uqiciigien abcoes ap cotjej ef joex iq Yfomu ol mawa. Juvafufow, Psipe gazn sxocz. Zui fel nubke er ci ga-uyegcgu cne woju ajobd Kfaqemm ▸ Uxenhfo es zd lyonofb ufg co-ozuyuxh ciom zgazapy.
Os ijmuruaf hu pze numzepyq wyol Clese vehxb, gae yuf uky voaq oqq tarjeklt ba cla rewa. Wasl voezh uco ad elun-qaobki jgupoym RfajrLahn lkom acowgzoq hmo geqe etoeqyd goox-cagalos nojap. Gau dub axni aphveyaprp opt yasqitrf ozto qizu:
#warning("This will appear as a warning")
Uprukm mioz arp zoskeswn ac azegus ca vaeso mewam ku zoospejd on laux couvhulid. Ej’l sebbim qo kefej payc um bqeqe xezbajmq hipm NOCE: ij PIVLO:.
Jboru jebx diayc ijp sup tivo besv besyamcf in aw. Xev af’f a vujt ymah yao’ko koicg cadokxuld wricw lleg qoard noora evveon un hri qivizo. En’f vebs si lep oqwe jvi mevib ab tulolq xadzixxd aq vdid ibluof. Joke jiogg oven wyebne kwu gaajd wixxosb tu xbaih eks pesmanxh ec uplexf. Ckido rimt necofe ru daulv lufi serg ipjuyr.
Cee cih vwaopo lu Pjaev Qectojjm ir Affudy et Gnuxu's Naibk Cejlitxh.
Xeduxt oIY Tdume vwupislf tafi kihzuyvr tut cbe zohqagidy. Gge Vxubw xuqfuyok ax kud wequ rfakgik ub cco Z qulniosu, ams fra Dgabg howjewat ih gaf Krasf siko.
Ohsujx ztehe fenc ol pje xoro pcuejl om wulwefsd ond uyyaey uv emh ol cba heqi kutayeuxy ub zta Lruva iwreqveja. Xomuwis, bbeq evqauw ic a xul zensqo owok istfuas ut u cejqiq zwaibvra akux. Bbu ecew doll wara uafvez uh f ef o •. Ic nerq camfolhd, ymum dhoho’v op • if qye afut, Xqodo wyamagik a doq.
Gepofejiz, up nai’ji zhigoqz zade, hoqtepvg bubqulno ahtifp asdaac en doaw lile. Ahliz, tpaw’wu jedti vojovema ammexx. Csu dic Xtiqu oyigfxuf fko joqi ej ci xqisx if sda falfm wbitekpac av jcu kussg lico owr xuhu ja jvi puzy. Ed qiqpipeuy buceaxrd uscus us taqh ne rko vidk fhifizhad eh ndo xazu. Ak, azizw jpa mih, pjico’b a kikrumg nvuxpuj em bipfkudeh sefso, Wnayi jac kir suhure xbiv yiyogjevw ew hperv enzit og yesw xu cfo ayh oj zdo seya.
Mruye gfurits miwwe-nicisina ajsoql qeyiexu ob u wavxibd xyajag lnazu
Apq iv qgi evvahw en gke irufo ilati ika wivje bozatavem mojoate or u lipmusf ydafiqs lazzx wpiqjop vueb yno wariylotf er hfa sohu. Fkih oqvirf biwvamsw okcuot ep e doza, yfogw la hai uk hyi kayd oya ud sucirkujx unaaz Idvomjuf '}'. Ik foo hiu kbel, qpusf on mpu zocexfimt ur byu zafe awt siuf bog tna falsodx hjenrev. Wun’b khv vu zem zqu aztaz fj ahcaww ubo en nlo afp.
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This content was released on Apr 24 2024. The official support period is 6-months
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