That example, in a statically-typed language could be handled with overloading or polymorphism, which are both far more concise IMO. C#'s standard library, for

That example, in a statically-typed language could be handled with overloading or polymorphism, which are both far more concise IMO. C#'s standard library, for example, has common interfaces for collections so the code will still work on all kinds of lists, arrays, etc.