Using built-in contains function. about exswift HOT 1 OPEN

func contains <R: Equatable> (element: R) -> Bool {
    return Swift.contains(unsafeBitCast(self, [R].self), element)
}

func contains <R: Equatable> (element: R) -> Bool {
    let seq = SequenceOf<R> { () -> GeneratorOf<R> in

        var next = 0

        return GeneratorOf<R> {
            var item: R? = nil

            while item == nil && next < self.count {
                item = self[next++] as? R
            }

            return item
        }
    }

    return Swift.contains(seq, element)
}