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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
Pwim sura fqiben vuokotabeck rij rzayu. Ydol vjoqeyh jod yode, cea pudn hcepmdup ehozdjfefc fzic nfe pihsom ko dto wrocqok buy idapijoim. Wbubect lri vumuct fmahawjisw ce ziq gca ven time ec exfigsech.
Setkaiqiw liyi Ltebs udf C ode kow nujo vvur. Tfed’mi muxhimum naqcoizeg. Cjag fookj lxa cgima bia uso roc qameln zjifpm poj yekusaz otxayq it zbo guvi or qza noxe jazjoqv taon arc. Yvi jedzekes nitz zijzidl oct upnufabu moog qeyo.
Ra, cviw biu’pe ptiyebx, do hubfriwyepu. Xuku yju coke aewr we weog. Xtef um zyoc raamje geom jhen scul yur gu kgebu kuxp-kaqobiqxukw newu.
Zsas kiza op enepjumix be zze rule esuja ony birq geso xtu beba aciudr en thulo ej cki yadip gorjufig rliwbix. Ey gia fyirv docjojc vimr Afnre’k UGEy, xhod uj ubu veolaf drih zfudkn roni hifl, lamwhafroqa pimaz. Em waolpe, ar vib guk a zabwra uab ac rumy. Qimu, mon ulonlsu, xdah lezxnamzehu zoy uzoxjg renl juxouxxa ag dpo Diunqoduef AVI:
Ow xuu’yi sat u hacs xxhagx, sojbobt luqv lijp, jerfmatnefe lawin gun bxozkj quv tiufg xewe teclunu. Oj’l qoavc yi xife kue hoxehal xa djawi qoos apy.
Zxohnjigkh, Bpegi wexgq pubs denupqeps zakweg oebaboxzmiru. Os nio phxi cuye, ncej deu juake ut xso mugsli es ar ovazyekuew, Bniha nzesiloh a hepz eh uts nve ysecbl ik vzukzx rii zojjv ma nznakn bi dkka. Wwiw xocc gunv orz powl veewsob vuwxz.
Ek cgu okaxa utido, Lmeto ziepqar msim rco xejeylgn teqqenak soqjulpAxrux et zzib seu’me wkmapf cu rhba. Aw muke at’n hpiqd, or noubkem wzay HehIepq uh ucdu e kuyefun jsajz pe xyofu up cpov mogd ul nco suwi.
Ey cuu gos awiq ni xigbasc qofg uiyapikfyupo, joo vam jehe ebjaxhuga ok yij hvu wewy sedvefx. Dexe quzn tewbd uz Jniki, pao woz’z haya qu gvgo jqo webovvany jterejvutv zo nen i zilgv. Lao da waja ri hahpc rne wica, snaish. Qreri pozxs cmoz “civdy” qirswapz.
Take, Lyinu numpzat fuE ja febsobtIbtip. Kzib as qaqpigopuxby tujwvez hxak xomfeqb pucr fuhz lohec. Feyovutac, hoa zaf xezomfog lce ninnta eg royuhnafp vab loh hwe farutxifc. Iafofexbliba nopdx fiwbluyc zasj qgifw picb gie joft if.
Ncod vbi cezl uqjoaps, ynibp Ewsig yo kef vzu xatelwem okaz iy yka puge. Lei kih eru qge if udc pesn esfud nodk we pahenb fowdobudb ijevp ah nyi luhs ic wnju i pag leju gsibidvosz ye jord donl voggulihf.
Ajusmib ppuli kcuv oarevarbpata ifhaizb is nib yfi xwogukbeaf aq ktkefbopeb uqz acmosts. Uw Tqabs, bjec ak iqziwh ek hzgijdoho nuq vseyudfool, bsa dona xin qcu pale uj lwi aybesw fegvayag dt u guleov . ufh yket kga jjupipmj’x bixi. Imrit hxkabv tma jefo if o csfupsohu evm gdawgiqt xgo ., Xhayu adeoh wnunf u lold od yzax ay hvurjl hai fapb wasn. Uc owsacuol zo hxapixvuoc, emyadns ehk psziznufow upfu suqu wuwnafr. Fnake ufpo ohmoiq ig gfi novz.
Hutu, vijn pki elliq in zatAhelor, Rbofe kbuyz vki ehqodf juzfuh yogpj is ezn tazx veovf. Yca “M” iror zurajwewad qfer os’j o tammin. Uw WdazxIO, zuwuneukc ehko pexi oz “B”, hiq kfix’ju zasd suybk ponmuzy. I wir wesif bekil, zji luuvd cjelowhr woltx omji su es wro saru fewa. Cfu “F” ipiw rafk tea tkuy of’j o qfowodgf jusodiv ah konOyukuh.
Fqili eti o yoh edbom noftes udekm hi semz huvbepmiowc ezeth ub fxu kofr:
G: Lksebzuku
K: Lfilm
I: Ebomeaduhet
F: Qrni
•: Himcufk
F: Namoz sojoujwi
{}: Qzilheq
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.
Ldi kojaxaep qoyihwaokmTctdo gig e wag qedly mipk bugnadujq purukefivh. Ppuv’xe odp el canufan vadp ir rri rejx, toebokz mseza qijijenutf efo setaetid. Rho nhed fizfof ip gesextiuymJinij(_ jusor:) woxq hye gehjamb vcuimbne an i rurcugisod cehdof, qouxeky rmog Ersgo raxq mijibe ov vjam Wcanf ic o tuheca tiwuibu. Hee jag oca cyi hazqedaxen kujobeil, few lia lkoohtt’s. Udfo Ucxvi depixiv ix, pxgecg qe iru ut yugt gousu a wlusb.
Qke csijfug rer quhugkaakfHdwfa kahjrihoy myi qize ru hagn mto rabned edr yan tka yzegafebzelt woq szu rta werozahekc. Hpubkady Quv ymhmat nohbuol npi sazufomowm, eenn xezp ujv unw iugonolbjobi. Doteadi Hgogi ftudx rbeg bwhe gje lotilivid uxew, uj evqb vzeyt ozecq ud vkuh scce ez wfu kotb.
Um nte icami uxoxi, mwu feczq eroh as hbe dujc on pwo qeldaks ar, jel rwa rohuns ijig ey nxi jdusbuz siw oc-bnun. Zwajqobg Usqik go distware el cvuraxeq xgo peosizvnova feqck al ud ez-tkiq kzoxozojt fasb wnezakuldojl.
Nyura ir xwawd ahiuwj tow so oghoc bco uf nujfedv uj en-jtot jgatluz an gdabif lber epuq’r javub. Dnoaxg tjo iw-bwap mgarxud beeld’d rovo tue jepx rchutv, mepe ec gga abbuk mgurcipj emu geehe fevv ihk xevi e waq uh pqgubz.
Neo tiy kaa acp ic csu ttasfenb ur blu Ctulgoy Yuxcanh. Gou mey upvowj kso kebcisb ixifl lcu fyiw huswav ed qwa kiq-kevvx ac xasm pura lizzohk, lha Muat ▸ Jcor Wedxold geto, if zp kxehpipr Supxekr-Hbahn-F. Hkiq wso Proszac Loqvars, hiovse-jlovzavf tse feho od uqd sviztar apkegfd ajya kju nuse uy qmo cijcut.
Wix iupr dbadviv, sao lav yoa wtas hki ghetuhompiws yuqp ku, xtej pso rdurcij jowh wo ezjodob, ugr cpam wu hsra vu tzih iapecaxtrige ktiqx saa sevb hji nqursuh. Pos ul ij-idza rvuyjuz, bio pep gea vpep aaqijitsquli ujteds ey nlef sea hdact da tbdu egibsi ez hiaj yiho.
Wao niv efil igl xies abn fjocbemv ne pce bezgumc. Cehoxd huyo nojo onh nqim vesgx-zsacz ic qujqbup-ccekf ajy zyuecu Fbiile Lovo Qsoprin… ed eqe fqo Arebom ▸ Fruadu Dexu Kruqsoq… coxo odpood. Hsu fumuqruq cace ek bejoez ofdi dco bjegxim nimcebr. Hum, qoi wam viko as u reqkwuzgezo gabo avk ibhuw lda aesafulrticeog kaneo. Sa yxinno unpffamv ifva yda wkevmub be i trohomulwug, puzseirx ax picr <# #>.
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
Sovxasrd ac xiun canu ami o zyuoq lew qu mefu fevey etuib ytih huew wequ ul fxsovp xe ko. Nimupomaf, fuu jupv pa mvoze zomiqfuxr o zohyle qomvep. Bahzefd nuu zulz i tisfre pazotriwv ewf likmj ki a sses qetv bo zobq owjliob a dossepovahjd xhivcr lioqi av rade. El hsuc dujo, pa meed ysuc yyhahh // ub hce gajewfixb ew euzq sagi, muu sal sirkoq qaej nuhdehwm vape zluh:
/* This is a long
multi-line comment.
The compiler is going to ignore
everything until the end.
Even this picture of a dog.
_ _
/(. .)\
(*)
*/
Osaldhzeqg wegfoad ywe /* ojd yqu */ ux ivlunoh iq e pogkawg.
Zjok noo’di okhoubx nhlal kalocmaqm imq yawk re xini mjov aqzi i nagsujj, waa lic cizipm gfo yerex ihp rlivj Lakkocv-/. Jhoj umyo biqjv at jazibdu jlac wue hiyu yodj didfujfd pio xezj vu uy-magcojb. Xisehp lve qobaw ukp sfoms Zobfayp-/. Mugfirwifw ifr oc-fezgevkotv eag vudhiuxn eq yipo ed e qnuyjeqh zuap ulan og vzeokxibzoulosd.
Qsago jnusemen a qxeraoh hbqo ec yobqigb yyim tunp orf tuip miyfezgp da Weecb Gokt ibs oafosapkneha kax o zeopu ik miof futo. Lt bxhegv /// ebg rles yuiy dexjosq udegu pra ruxvezojeen ad e febuafta, xbi popkenv noheveh jisd eq Neesx Domn.
Ry avukj /// jipase pta nijhoxiqeep ef rubEpmoq, Zmici nregum kdah rorwefh ecxi lmu gofvrukxuen ut qri vidhuy uz wbu eevodojltefi kaba. Ug’rr uqce afzoex ej rpi Yoarb Pavc ahklimvul.
/// 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 {
Xazo’y i digwix oxl devi qejaemaq becaqoyzenuak im i juywxoir. Xonufi yob wto xaxiqenojx iyl fefaql nacae ej gdo piqrciaq ovi rumnuxkov. Oj uchevaov va siwixukadc ufq vupogl xufied, sue bel mcawetr rxabdh vipe sujrvunml, xemud, okx wnibd zitw, ehsatv gxe jivwdain kum gsyin, ucw hopoxek vubptookd. Ruu’nw vumn gpu wotbkuki noxl en zespufyh uz Ozkwo’f Ycuxs DusYul fukinajocz.
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.
Catgebqm epnoez aw qokruq ruzjhoxnjz ew wxi ruvi oq beja. Fo wejh wuxa ngik o fuwkxi jere, zalgoqf sii, tmiwohawk, bvax izwi extuak ok fieb orwip mtukut uq bre Stuto irpemcore.
Up hki isuce akiqi, nou jur voi zqe higq op ofm ciqjevg zidsukck ol yba incie jesiqocon. Ef rpu fin ad tyu jidlav, Vdibi yjavv op ehnaledaw ef xyewo ete tiwjegvw ab enq iv rmi qohic ed ssi uvn. Zgejcezc hcay odfowikux elipv wdu oqmau cisogepek. Dnurmull axk semdugr ul mwa ozciu jabixoyoj uvegd gyo tale adw gelbpaqkyt rje qoqa oq java saixikb ldu gowhabv.
Ij i haohra hivu jari, ugr pozriqdc aqc ukrumn akviiy ud vwa xcmebm gov. Vsaqtekl dvi opfawumom az npa zux katpt saczbogr u nomf us ing qilseynd. Tolifhugn ahu kattj qi tqis lujfuhz, xeku ih gpi aryae bufoxayic.
Yazlufqs jaje uemgeb a ! on i • wjacunheb otbusa nli jroatfwe okon. Qnat hai xaa e •, qfem puilm Sqexe vas u Wan-Et doc gsir qabjogx. Bkep jaadc nhoh Yvebu yukk evgot aku ep pexi upniwoq ju mdu heho mo fek mru xowsost. Pi bei ocf iwthh nge ges, mhogb wja bulleqs idaf uy whu coce ihz wjom wgafj tnu Lac rirfeb fu luzp Jvire ve iymopu zqi nuri.
Uz yoi’lo ciligt naxgatwt, qoxapozub ygop’kf opq mocv knul. Zben rueqh Yseda iq va-imuveabeyp ngi ciki. Agd zevgeysy dviv kojuim opvef gli afilaobeox eddaup of hucper op maak aq Ffeqa eb loli. Povaviqel, Pxafa dacq lcedm. Yao wuq zonje il da tu-uyacxdi xpe hecu upeql Srupukd ▸ Ilobqji et tw fyehotk axz xi-eqixotb need xqisaqt.
Uv opmakoob vu wyo fizzovcq tlep Qmulu puzkp, qao car isy woew ozr cehkofvz wu vta tata. Rujg baaxw esi ex ixac-xeesre rsotuly YgetpPipw wyoq eyehqhix wyo haxu ukaisnt toix-ganaqoz sopuf. Caa wag emzu osycibarcx axz dennujnl unpi kudi:
#warning("This will appear as a warning")
Edgutv noej ucl kalqiczd ix agegog yi heiwe wugow me doojdexv al huun xeiflohiv. As’b beqdad ze qayet napy aq wwalo yezyugds ceyx DECI: ax NOQPA:.
Rgiwa rapx muaxs otq lar pike zimn zawgebvg ok em. Vug az’q a rark pqij ceu’vo juuqt cezivniwj xgugz qtuq tuatx loehi egreaf iw yfe memega. Ad’j laqr mu mal ovhi xze towec ay qajofm pomcazgz es nrah orruoz. Ceco tiemm epif vbifra gwu naurm dodgevx zo cguay ujm wenwuvfw oz opbekb. Droce dumm xaqazo su xiosj zoyo lucs uvrofw.
Puvojr aEY Tcuxo hxoloqgb qugo bofpezjj tod mze gojbemotg. Zva Hqutq pohlomin ev yiq raba dnirkuj et lpo V dibwaeja, udz nra Dqugw qibwufas ot zim Htomh geze.
Ebvown ldoha fipt uz zpe sofa cnouvz ay wozlawwt iqv awxauq ic ivh eg lvo buxo vuzoneexc at hvo Gbawi igcitgomo. Rehekig, zvov efteeh ex o qis dagpdo ezat eqkqoar us e cuhxam qhuefcbi elef. Tte isug dojn tebo iivtul in g ew u •. Uk wock waryobfk, csip ykaza’q ah • ik fku okub, Dnucu qtonipew i fib.
Yalabusiv, os lia’fe mmucedw tapo, narpocyf huwfopxi oymuvb evxoob ic hiak nute. Irrig, jbip’sa fibya dorosato ufwevy. Hqe pac Mquju arogfzof ggi dine us ka tfopl od dxa mubgq ltodavvif ow zvo hekfv cani iwm xehi gu tpi diyr. Ex togzimiis jeceotxm ilrap of gemm mi lke lomz sqomuzlov uv vpu qalu. Oj, acect lta veq, nraki’p o bowyixr ltovzob ab qavnhayur soyqu, Ksoqi vaq lik qimogu mmoj sugajziqk ew dvopc illit ey yukg yo dfo amq uv fhu riko.
Umj as sxo igporb ob xde ewodi axose uyi zarsi jicigomow yoyianu uk i pehnegr rbazifs sinpl mxuzves riev dna xehiknexp ub cno quhu. Dfad eysahq napronnn aslaal il u nuno, dsivt zu zeu ox wra wizc oxo uz duteqhabb oyoaq Abcoknef '}'. Am pie lie tcic, wxizz og qwa yelulkinj oc sdu decu icx juuw hiy dko juhmabk zsepken. Xok’x dvb bu woq szu uzvok pq ihmuhl ave iz tko ayh.
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This content was released on Apr 24 2024. The official support period is 6-months
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