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        push @INC, \&my_sub;
        sub my_sub {
            my ($coderef, $filename) = @_;  # $coderef is \&my_sub
            ...
        }

        push @INC, [ \&my_sub, $x, $y, ... ];
        sub my_sub {
...
            my @parameters = @$arrayref[1..$#$arrayref];
            ...
        }

        # In Foo.pm
        package Foo;
...

        # In the main program
        push @INC, new Foo(...);