#!/usr/local/bin/perl -w # # Figure 16.3, p162 # # how to do this ? use Tk; $mw = MainWindow->new; $country = "Japan"; &watch($country); $country = "Great Britain"; sub watch { my ($name) = @_; my $watch = $mw->Toplevel; $watch->Label(-text => 'Value of $name: ')->pack (-side => 'left'); $watch->Label(-textvariable => $name)->pack(-side => 'left'); # $watch->update; } MainLoop;