// RUN: %target-typecheck-verify-swift

// Simple enumeration type
enum E1 {
  case First
  case Second(Int)
  case Third(Int, Double)
  case `default`
}

var e1: E1 = .First
e1 = .Second(5)
e1 = .Third(5, 3.14159)

e1 = .default  // SE-0071

// Generic enumeration type
enum E2<T> { // expected-note {{'T' declared as parameter to type 'E2'}}
  case First
  case Second(T)
}

var e2a: E2<Int> = .First
e2a = .Second(5)
var e2b: E2 = .Second(5)
e2b = .First
var e2c: E2 = .First // expected-error{{generic parameter 'T' could not be inferred}}

// https://github.com/apple/swift/issues/55797

struct S_55797 {}
extension Optional where Wrapped == S_55797 {
    static var v55797: Self { .none }
}

func f_55797<T>(_: T?) { }

f_55797(.v55797)