     #endif
 
     #if os(iOS)
-    @available(iOS, introduced=8.0)
+    @available(iOS 8.0, *)
     public func removeSharedPassword(account: String, completion: (error: NSError?) -> () = { e -> () in }) {
         setSharedPassword(nil, account: account, completion: completion)
     }
     #endif
 
     #if os(iOS)
-    @available(iOS, introduced=8.0)
+    @available(iOS 8.0, *)
     public class func requestSharedWebCredential(completion: (credentials: [[String: String]], error: NSError?) -> () = { credentials, error -> () in }) {
         requestSharedWebCredential(domain: nil, account: nil, completion: completion)
     }
     #endif
 
     #if os(iOS)
-    @available(iOS, introduced=8.0)
+    @available(iOS 8.0, *)
     public class func requestSharedWebCredential(domain domain: String, completion: (credentials: [[String: String]], error: NSError?) -> () = { credentials, error -> () in }) {
         requestSharedWebCredential(domain: domain, account: nil, completion: completion)
     }
     #endif
 
     #if os(iOS)
-    @available(iOS, introduced=8.0)
+    @available(iOS 8.0, *)
     public class func requestSharedWebCredential(domain domain: String, account: String, completion: (credentials: [[String: String]], error: NSError?) -> () = { credentials, error -> () in }) {
         requestSharedWebCredential(domain: domain as String?, account: account as String?, completion: completion)
     }
     #endif
 
     #if os(iOS)
-    @available(iOS, introduced=8.0)
+    @available(iOS 8.0, *)
     private class func requestSharedWebCredential(domain domain: String?, account: String?, completion: (credentials: [[String: String]], error: NSError?) -> ()) {
         SecRequestSharedWebCredential(domain, account) { (credentials, error) -> () in
             var remoteError: NSError?

    public var comment: String? {
        return options.comment
    }
    
    @available(iOS, introduced=8.0)
    @available(OSX, unavailable)
    public var authenticationPrompt: String? {
        return options.authenticationPrompt
    }

        options.comment = comment
        return Keychain(options)
    }

    @available(iOS 8.0, OSX 10.10, *)
    public func authenticationPrompt(authenticationPrompt: String) -> Keychain {
        var options = self.options
        options.authenticationPrompt = authenticationPrompt
