title: Can I change the Associated values of a enum?
body: <p>I am reading the Swift tour document, and facing a problem.
  Here is the code:</p>
  
  <pre><code>enum SimpleEnum {
      case big(String)
      case small(String)
      case same(String)
  
      func adjust() {
          switch self {
          case let .big(name):
              name +=  "not"
          case let .small(name):
              name +=  "not"
          case let .same(name):
              name +=  "not"
          }
      }
  }
  </code></pre>
  
  <p>The function <code>adjust()</code> won't work, I wonder if there is a way to change the  Associated value of an enum, and how?</p>