title: How to init a struct in swift 4.2
body: <p>What I want:
  To initialise a struct before use. But I really don't know how, even after a lot of trying and searching.</p>
  
  <p>Example of the struct:<br></p>
  
  <pre><code>struct Person: Decodable {
      let name: String
      let age: Int
  }
  </code></pre>
  
  <p>I want to use this struct global in my script. The way I think it would have been is like this (but it does not work, because of line 3):</p>
  
  <pre><code>import UIKit
  class ViewController: UIViewController {
      let personExample: Person()
  
      func configure(person: Person) {
          self.personExample = person
      }
  
      override func viewDidLoad() {
          super.viewDidLoad()
          print(self.personExample)
      }
  }
  </code></pre>