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  1. Swift
  2. SR-4559

'self' in property initial value expression refers to class (?)

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    Details

    • Type: Bug
    • Status: Open
    • Priority: Medium
    • Resolution: Unresolved
    • Component/s: Compiler
    • Labels:
      None
    • Environment:

      macOS 10.12.4, Xcode 8.3.1

      Description

      Given a function f that takes Any in one of its parameters, passing self in a call to f is allowed in a closure that initializes a let property.

      The compiler should raise an issue for using self before all stored properties are initialized and the issue should disappear when the property is transformed to a lazy var. But the current behavior is that self is casted as func `self`() -> Self and the compiler does not complain.

      The following code reproduces the issue:

      import UIKit

class A: NSObject {

  private let control: UIControl = {
    print("I'm not lazy")
    let control = UIControl()
    control.addTarget(self, action: #selector(valueChanged), for: .valueChanged)
    print(self) // prints "(Function)"
    doSomething(with: self)
    return control
  }()


  @objc private func valueChanged() {

  }
}

func doSomething(with a: Any) {
  print("called 'Do Something'")
}

A()

        Attachments

          Issue Links

          is duplicated by

          Bug - A problem which impairs or prevents the functions of the product. SR-4865 target self should be illegal in property constructor

          • Medium - Has the potential to affect progress.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SR-6895 Timer property with initializer and `self` target causes crash at runtime

          • Medium - Has the potential to affect progress.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SR-7198 Using self in computed let

          • Medium - Has the potential to affect progress.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SR-7368 Bugs of self-referencing Default Property Values in subclasses

          • Medium - Has the potential to affect progress.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SR-7981 `self` available without backticks in let initialization closure of NSObject

          • Medium - Has the potential to affect progress.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SR-8440 Using self inside a let initializer

          • Medium - Has the potential to affect progress.
          • Resolved
          relates to

          Bug - A problem which impairs or prevents the functions of the product. SR-4138 Static properties are allowed to use without qualifier in initializer of instance property

          • Medium - Has the potential to affect progress.
          • Open

            Activity

              People

              Assignee:
              Unassigned Unassigned
              Reporter:
              mouhcine Mouhcine El Amine
              Votes:
              6 Vote for this issue
              Watchers:
              13 Start watching this issue

                Dates

                Created:
                Updated: