How do you define a class in Silk test

How do you define a class in Silk test?
How do you declare it?
Is there any menu function in silktest to invoke a class?
Please answer all the above questions.
Its urgent

[B]Question asked by visitor aparnay[/b]

winclass <classname> : classname(useridentifier)

ex:[+] winclass HtmlPushButton : HtmlPushButton
[ ]
[+] void Click(int i optional,int j optional,int k optional)
[+] if (!WaitTillNotExist (this, Agent.GetOption (OPT_APPREADY_TIMEOUT)))
[ ] RaiseError (E_CANT_EXIT_APP, "Application cannot be exited")
[+] else
[ ] derived::Click()
[ ]
[+] boolean bexists()
[+] if (! WaitTillNotExist (this, Agent.GetOption (OPT_APPREADY_TIMEOUT)))
[ ] RaiseError (E_CANT_EXIT_APP, "Application cannot be exited")
[+] else
[ ] return derived::Exists()
[ ]
[ ]