know type of variable in Swift

Question

How can I identify the type of variable in Swift. For e.g. if I write

struct RandomStruct.... - the type should give me struct and not RandomStruct

or if I write class RandomClass... the type should be class and not RandomClass.

I have tried using Mirror.subjectType and type(of:) both of which gives output as RandomStruct and RandomClass

Answer 1

You were close with use of Mirror: you can look at the displayStyle property (of enum type Mirror.DisplayStyle) of the Mirror reflecting upon an instance of your type

struct Foo {}
class Bar {}

let foo = Foo()
let bar = Bar()

if let displayStyle = Mirror(reflecting: foo).displayStyle {
    print(displayStyle) // struct
}

if let displayStyle = Mirror(reflecting: bar).displayStyle {
    print(displayStyle) // class
}

Just note that .optional is also a case of the DisplayStyle enum of Mirror, so be sure to reflect on concrete (unwrapped) types:

struct Foo {}

let foo: Foo? = Foo()

if let displayStyle = Mirror(reflecting: foo as Any).displayStyle {
    // 'as Any' to suppress warnings ...
    print(displayStyle) // optional
}