Access properties via subscripting in Swift

Question

I have a custom class in Swift and I\'d like to use subscripting to access its properties, is this possible?

What I want is something like this:

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Answer 1

This is a bit of a hack using reflection. Something along the lines of the following could be used.

protocol PropertyReflectable { }

extension PropertyReflectable {
    subscript(key: String) -> Any? {
        let m = Mirror(reflecting: self)
        for child in m.children {
            if child.label == key { return child.value }
        }
        return nil
    }
}

struct Person {
    let name: String
    let age: Int
}

extension Person : PropertyReflectable {}

Then create a Person and access it's keyed properties.

let p = Person(name: "John Doe", age: 18)

p["name"] // gives "John Doe"
p["age"] // gives 18

You could modify the subscript to always return an interpolated string of the property value.