Enum case cannot be used as an instance member

Using Swift
1

Take this example code which is accepted without comment from the compiler:

enum SampleEnum {
	case anOption
	
	func process() {
		switch self {
		case .anOption: anOption()
		}
	}
	
	fileprivate func anOption() {
		// stuff
	}
}

However moving the anOption() function out of the enum type results in an error:

enum SampleEnum {
	case anOption
	
	func process() {
		switch self {
		case .anOption: anOption() // Enum case 'anOption' cannot be used as an instance member
		}
	}
}

fileprivate func anOption() {
	// stuff
}

I'm curious if this is intentional behavior here or a bug of some kind? (Feels like a bug to me, tbh.)

2

I don’t know if it is intentional, but the compiler always finds static members first and prefers them over the global scope, resulting in errors.

var property = 0
struct Structure {
  static var property = 0
  func useProperty() {
    property = 1 // Static member 'property' cannot be used on instance of type 'Structure'
  }
}

What you can do is tell it where to look explicitly:

MyType.property = 1
MyModule.property = 1
1 Like
3

I wouldn't say it's a bug. Here's another example:

struct Foo {
  static let bar: Foo = .init()
  
  func doWork() {
    bar() // error
  }
}

func bar() {}
1 Like