@swift-4.1.3 @swift-4.2.4

struct A { var strings: AnySequence<String> { return AnySequence { () -> AnyIterator<String> in var buffer = staticStrings ?? [] return AnyIterator { if let first = buffer.popFirst() { return first } return nil } } } } let staticStrings: [String]? = ["1", "2"]

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