#!/usr/local/bin/perl -w
use Tk;
use Tk::ErrorDialog;
# $SIG{__DIE__} = sub { print "die(",join(',',@_),")\n" };
sub one
{
 shift->BackTrace("dying");
}
sub two
{
 my $w = shift;
 eval { one($w) };
 $w->BackTrace($@) if ($@);
}
my $mw = MainWindow->new;
my $b  = $mw->Button(-text => 'Moan',
              -command => sub { after(1000, \&two, $mw) })->pack(-expand => 0);
MainLoop;