title: Swift filter array of objects
body: <pre><code>class book{
      var nameOfBook: String!
  }
  
  var englishBooks=[book(),book(),book()]
  var arr = englishBooks.filter {
      contains($0.nameOfBook, "rt")
  }
  </code></pre>
  
  <p>I'm using this filter but with error cannot invoke filter with an argument</p>