jsdIStackFrame
method overview boolean eval(in astring bytes, in autf8string filename, in unsigned long line, out jsdivalue result); attributes attribute type description callee jsdivalue function object running in this stack frame.
... scope jsdivalue top object in the scope chain.
... thisvalue jsdivalue |this| object for this stack frame.
...boolean eval( in astring bytes, in autf8string filename, in unsigned long line, out jsdivalue result ); parameters bytes script to be evaluated.

nsIEventListenerInfo
return value if jsdidebuggerservice is active and the listener is implemented in js, this returns the listener as a jsdivalue.