Hi,

This is a good question. In this case the error is telling you that some widget requires a '-label' parameter and did not get it. (The prime example of this is the command method of a Menubutton widget, which if left without a label will produce this exact error.)

Normally use Tk::ErrorDialog will produce a stack, with useful information, but neither that nor a custom Tk::Error sub will produce useful information in the example that I gave.

sub Tk::Error
{
    my ($widget, $error, @locations) = @_;

    print "Widget:\n\t$widget\n";
    print "Error:\n\t$error\n";
    print "Locations:\n";
    map { print "\t$_\n" } @locations;
}
[download]

If you or anyone else comes upon a way to trap this kind of (rare) error that occurs outside of Tk's built-in error mechanism, I'd like to see it. In my experience this kind of thing is how pTk earns its undeserved bad reputation.

Update: belg4mit snuck in a response a bit before me {g}, but I wanted to say that I have version 3.078 of Widget.pm as well and it does indeed produce this exact error at that line number if perform the action I describe above with the command method of a Menubutton widget. That is why this error appears to happen outside of Tk's Error handling mechanism.

Good luck,
{NULE}
--
http://www.nule.org

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