Adding optional value to [Any], got compiler warning - expression implicitly coerced from Double? to Any

Question

I'm currently learning the type "Any" in swift and have come up with the following code

let optionalDouble: Double? = 45.1
let things: [Any] = [
    0,
    0.0,
    1.1,
    optionalDouble, //expression implicitly coerced from Double? to Any 
    -4.0,
    ("hello", 1),
    Movie(name: "Titanic", director: "James"),
    {(name: String) -> String in
        return "hello \(name)"
    },
    {},
    ["one": 1, "two": 2]
]

However, when I tried to add an optional Double value to the [Any] array, swift compiler displayed an warning saying

//expression implicitly coerced from Double? to Any

I thought type Any can represent everything and an array of type [Any] can contain everything. So why the warning message?

Answer 1

It's only a warning. The compiler wants to make sure you know you're doing an odd thing, wrapping an Optional inside an Any.

In the line that's giving trouble, write optionalDouble as Any to suppress the warning.