Generalized accessors

Transcript

1. subscrit
   get set
   

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2. get
   let nums = Array(0..<10)
   let x10 = nums[3] * 10 // `get`
   print(num)
   subscript(index: Int) -> Element {
   get {
   let element = // `index`
   return element //
   }
   set { ... }
   }
   

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3. set
   var nums = Array(0..<10)
   let num = nums[3]
   nums[3] = num * 10 // `set`
   print(num)
   subscript(index: Int) -> Element {
   get { ... }
   set(newValue) { // `newValue`
   // buffer
   = newValue
   }
   }
   

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4. Swift 4.2
   mutableAddressWithPinnedNativeOwner
   Swift 5
   read
   ,
   modify
   yield
   co-routine
   

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5. read
   // CoreAudio.swift
   subscript(index: Index) -> Element {
   _read {
   yield ((_audioBuffersPointer + index).pointee)
   }
   }
   modify
   // Array.swift
   subscript(index: Int) -> Element {
   _modify {
   let address = _buffer.subscriptBaseAddress + index
   yield &address.pointee
   }
   }
   

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6. yield
   subscript(index: Int) -> inout Element {}
   inout
   Rust Lifetime
   Rust
   Swift
   

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7. yield
   

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8. !
   

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