This is an example of how to use the propertyWrapper attribute to autocapitalize strings in swift

PropertyWrapper-Capitalized.swift

@propertyWrapper
struct Capitalized {
    var wrappedValue: String {
        didSet { wrappedValue = wrappedValue.capitalized }
    }
    
    init(wrappedValue: String) {
        // we need to explicitly capitalize any string that was passed into our initializer
        // since property observers are only triggered after a value or object was fully initialized.
        self.wrappedValue = wrappedValue.capitalized
    }
}

struct User {
    @Capitalized var firstName: String
    @Capitalized var lastName: String
}

let andres = User(firstName: "andres", lastName: "raigoza")

print(andres.firstName) // Andres
print(andres.lastName) // Raigoza