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  • Advancements in the Objective-C runtime

    Dive into the microscopic world of low-level bits and bytes that underlie every Objective-C and Swift class. Find out how recent changes to internal data structures, method lists, and tagged pointers provide better performance and lower memory usage. We'll demonstrate how to recognize and fix crashes in code that depend on internal details, and show you how to keep your code unaffected by changes to the runtime.

    Ressources

    • Objective-C Runtime
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    Vidéos connexes

    WWDC20

    • Unsafe Swift
  • Rechercher dans cette vidéo…
    • 5:37 - Use the heap command to calculate memory savings

      heap Mail | egrep 'class_rw|COUNT'
    • 7:35 - Use the APIs

      class_getName
      
      class_getSuperclass
      
      class_copyMethodList
    • 14:38 - Use the APIs

      method_getName
      
      method_getTypeEncoding
      
      method_getImplementation
    • 21:52 - Use the APIs

      if ([obj isKindOfClass:[NSString class]]) {
          // a string
      }
      NSUInteger length = [obj length];
      
      
      if (CFGetTypeID(obj) == CFStringGetTypeID()) {
          // a string
      }
      CFIndex length = CFStringGetLength(obj);

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