syntax - How do I check if a var is a Tuple in Swift? -

reading type casting section of swift guide see use is keyword type check variables.

func isstring(test: anyobject?) -> bool {     return test string } 

it seems when try similar check tuple containing 3 nsnumber objects, receive 'tuple not conform protocol anyobject'. there way check if variable contains tuple?

func istuple(test: anyobject?) -> bool {     return test (nsnumber, nsnumber, nsnumber) // error } 

you can't use anyobject here because tuple not instance of class type.

• anyobject can represent instance of class type.
• any can represent instance of type @ all, including function types.

_{from the swift programming guide - type casting}

instead, try using more general any type:

func istuple(test: any?) -> bool {     return test (nsnumber, nsnumber, nsnumber) }  istuple("test") // false let tuple: (nsnumber, nsnumber, nsnumber) = (int(), int(), int()) istuple(tuple) // true