func foo<T>(value: T, type: T.Type) { switch type { case is Array<String>.Type: print("strings \(value as! Array<String>)") case is Array<Int>.Type: print("integers \(value as! Array<Int>)") default: print("unknwon") } } let ints: [Int] = [] foo(value: ints, type: type(of: ints)) // integers []
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