title: More than 8 parameters in combineLatest using RxSwift
body: <p>Is there any way to put more than 8 observable in combineLatest in RxSwift?</p>
  
  <p>Here is my current implementation:</p>
  
  <pre><code>let registerUserParameters = Observable.combineLatest(
          firstname.asObservable(),
          lastname.asObservable(),
          email.asObservable(),
          mobile.asObservable(),
          addresses.asObservable(),
          cities.asObservable(),
          pword.asObservable(),
          confirm_pword.asObservable(),
          instagramid.asObservable(),
          facebookid.asObservable()) {
              ($0, $1, $2, $3, $4, $5, $6, $7, $8, $9)
      }
  </code></pre>
  
  <p>I found out that combineLatest only accept up to 8 parameters based on its function.</p>
  
  <pre><code>public static func combineLatest&lt;O1, O2, O3, O4, O5, O6, O7, O8&gt;(_ source1: O1, _ source2: O2, _ source3: O3, _ source4: O4, _ source5: O5, _ source6: O6, _ source7: O7, _ source8: O8, resultSelector: @escaping (O1.E, O2.E, O3.E, O4.E, O5.E, O6.E, O7.E, O8.E) throws -&gt; Self.E) -&gt; RxSwift.Observable&lt;Self.E&gt; where O1 : ObservableType, O2 : ObservableType, O3 : ObservableType, O4 : ObservableType, O5 : ObservableType, O6 : ObservableType, O7 : ObservableType, O8 : ObservableType)
  </code></pre>