Querying about the type of a given widget

["Cogan, Gil" <gil cogan intel com>]

Hi,

I'd like to query whether a certain Gtk object is of a given type/class 
Example:

my $widget = pop  @widgets;
if $widget is an entry widget do this else do that.

I looked in "Types - Handle run-time type creation", which is in the GTK+
reference manual, but in vain.

Thanks for your help.

Gil.