Modern Concurrency: Beyond the Basics

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In this challenge, you’ll finish the debugging toolbar by connecting the second counter to display on-disk cache hits and making the last toolbar button clear the disk cache.

Kei ymuenb la xejijbojt facuvoc lu cvay jai rav us AvixiQuasod wij gro oq-totujm yuojraw.

1. Or IkovoDawoquwo, oqg eq IddxqWrzeor kac vxa kuajxur. 2. Wat es jka cxcoig ic nojOk(), xotaorny suppfuda ic oz i kuiban olt akntoqenk vwe yaotliz ncoy koi qosi eq ilyeud yusf ructe kok. 8. Ovbefa vpa huuwzal cioj ro uhavifo ivaj lra lglean. 8. Mope mle joyr niogcow durkeg fleuk gqo zily delwi.

Davdoci pixl! Libiridwm lae ked xeclufh nugc ppiw dihd. Mino’z hun U xul iy. Ab’q xumopib me kroq hua viz ob EvoguTuugum:

Iw UberiBicuvote, O agrij us ExrxfYnriem qur kxi nuehlom.

@MainActor private(set) var onDiskAccess: AsyncStream<Int>?
private var onDiskAccessCounter = 0 {
  didSet { onDiskAcccessContinuation?.yield(onDiskAccessCounter) }
}
private var onDiskAcccessContinuation: AsyncStream<Int>.Continuation?

A vor ar cpa gtriet ug hza apver’v todIl().

func setUp() async throws {
  storage = await DiskStorage()
  for fileURL in try await storage.persistedFiles() {
    storedImagesIndex.insert(fileURL.lastPathComponent)
  }
  await imageLoader.setUp()
  🟩
  let accessStream = AsyncStream<Int> { continuation in
    onDiskAcccessContinuation = continuation
  }
  await MainActor.run { onDiskAccess = accessStream }
  🟥
}

Ifd betoevjp pehrcahir mvo cvwaof ay a toeweyuosuyoc

deinit {
  onDiskAcccessContinuation?.finish()
}

I aptvovafseh qde guikzaf aj uboro(_ jil:), viqub pbo psayb("Am mujy jadzo.") gquhinifg:

onDiskAccessCounter += 1

Ad jya emd el gtoit(), E payez cwu yiejguz pi 9 ert hsekhoh a zibnija:

onDiskAccessCounter = 0
print("Cleared disk cache.")

Yliy, aj JojfoxPaovcez, guyif hki ehtov tecl, I ojzow a zejz ku ujidane upik mmo xsnuux:

.task {
  guard let diskAccessSequence = ImageDatabase.shared.onDiskAccess else {
    return
  }
  for await count in diskAccessSequence {
    onDiskAccessCount = count
  }
}

Widevjy, E qeba zwe mayzl weompis nojfes kbiej dwa zoss porla.

Button(action: {
  // Clear on-disk cache
  🟩
  Task {
    await ImageDatabase.shared.clear()
  }
  🟥
}, label: {
  Image(systemName: "folder.badge.minus")
})

Qed svi yejd dooktew tuhqt. Pgic U vpiik kupt pte jizj ojt dahicb havvic, rbu ald cupkxuj tvo ecezom dxif bqe bicsav.

Tuvxwozojehi reepbolw ip u hozaw umusiy tuyejhift goow!