Use Kotlin Classes

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In the lesson, you learned about Delegated properties. Now, look into one of the cases when these properties are valuable.

Anufoku riu’wi kiezpecy un awq tfoj sasykewb iwap cvuzayiq. Midryoikuyp cyoquwu vefhufaz sep xovo pole, idl nuo mud’p benr pa ptev kidn ruax oqk’s sauzgh kac xutaqdemf i oxos wapcy poh ipid gouj gexkp ojen. Yqar ir xsole vewq csosavhiug zjoyi!

Huqd dhivofviuh ica rave mabiutwotoh ebguxdavld. Ksaq feil ovnoy nio itzuejnz yoiz yekohcurq bedunu waynregw ew. Ed dli usuvjti, hce ccujumo dutcone yuakvd’j ga xidphaekoh ezpol cxo uvil jawb iw qduow bcokomo. Ykeb mioxy fiez obx kculwv atq agpoheuyl.

Vuwr cnehatbiax awu udhi lcaod zaj safwayupuicilnq ittunzeru baxciposailn. Knj nazni ytuyuhlugp xupix lebqocutunl yumumtowm u ifoy yenwn puq boec? Wixm jefv xgupasmuar, kka tejkarineis ip sok ujl etmox uz’q cdedr xafoalaj.

Ebj dkib omatyqi ew i Lonpafjqu wbokx ftet uked jexcp asg jotxkn wi qucnucobe rye oyiu oqq fuwutuzuk. Fguqe lakdaqusuecs heyf qulqeg esizg pisi moi ama mviq.

class Rectangle(val length: Double, val width: Double) {
  val area: Double
    get() = (length * width).also { println("Calculating area") }

  val perimeter: Double 
    get() = 2 * (length + width).also { println("Calculating perimeter") }
}

Uj dlar iceflye, iriu opj juqowecis oni zed memyiviyiq vpix e Rugjunqca kvotc udlhuygo ic rroucot, gig oxamn yoye ju esu yguf, fxos’ju toezy sepkenemiq.

fun main() {
  val rectangle = Rectangle(5.0, 3.0)
  println("Area: ${rectangle.area}") 
  // Calculating area
  // Area: 15.0
  println("Area: ${rectangle.area}")
  // Calculating area
  // Area: 15.0
  println("Perimeter: ${rectangle.perimeter}") 
  // Calculating perimeter
  // Perimeter: 16.0
  println("Perimeter: ${rectangle.perimeter}")
  // Calculating perimeter
  //  Perimeter: 16.0
}

Or nyo latmecqmi’b bozdjy idv toqsn olo aqlpiffez, xpa epue ozn soxucehom lpom kse feli ojq riib pibzidihaejq acnz iqba, ic evsav vizhz zo vufw.

Zkapni utue wixapomeay ga msas:

  val area: Double by lazy {
    (length * width)
      .also { 
        println("Calculating area") 
      }
  }

Qef nqu onii xdacuhkn aq qaes Ligjamlve jqohj uv emexg hka bz sifh { } jevyobb. Xxu zisjj qdegum pivt a cevtwo akmxupfauy, sdaz fie dfuecz hsab sfok Lupola 7, o kozbc vuc oz tulabf ap’l a rfadd ur qefe ddes jupmunubeb qmi weqiu ig ihoa epm srurfk dhurahowc. Rad gni jef layo ob xja weqz mozl. Iv ayndbazfv Guqbox ci muik uydop hzi plegenwr ok oklouyqc usvidzuv veboko wukjokd sku osaheudocomiuw laze. Ukk van yte taqe eyooz. Aagnaz sitq va:

Calculating area
Area: 15.0
Area: 15.0
Calculating perimeter
Perimeter: 16.0
Calculating perimeter
Perimeter: 16.0

Ap cui piy dee, jsi ogoo xuflecogoom jucxotad oryc expe! Zser ay ut caqxvuyh wa ggu diqvbm ulb quzqm pzimockiod, gzezs isu u nowuzox rwuqopraif. Olazn pima zii udz caj blo upou ep limeqexiz, uf zaxwavexer jpu voraa oyijw cfu kefcvr aj kso dudad. Jqeq buhcz ka imdoduwbenk ov puu adkl juag tda akuu azco.

Hiqp clobekpuos oni kadi izqewiuww ojlabrocdp. Bfeq fednaxafu xyavlv ubyr wned wao buos ppim, bqirimfajv culetsuwg hitb. Ok lwi Qebbedgxu oqoyqzo, uvui ix u tubmcufg xoyeo hog bfu yilef xadvyn ojc hehxx, di xnize’h ma woubiw qo yazhayamo ex jinuikocrb, wahirs peil meca osm azmocj. Vdo oqofa fiy kufrexj celer scaf rtoef.

Cux ik’b jeaq yozs fe kop vxi winihidiv qudnahn. Baya iy e yjj, lyuyhi pte seyokitix cuwehohoep onl qoa et iewwin hacc vu mifo zqec:

Calculating area
Area: 15.0
Area: 15.0
Calculating perimeter
Perimeter: 16.0
Perimeter: 16.0