Well, you really need to refresh the syntax stuff. You cannot pass function parameters with the coderef. Your command should be something like:

-command => sub { resort (\$sortflag, \@item) ; }
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I haven't used Tkx much, but I'm sure the rest of it should be something like this:

$tree -> configure(heading => "#1", -command => sub { resort (\$sortfl
+ag, \@item) ; }
 );
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