use My::Wrapper qw(wrap);

sub hello_world {
    my %params = %{shift()};
    my $q = $params{q};   # etc.

    # different stuff here
}

wrap( \&hello_world );

##</code><code>##

sub wrap {
    my ( $code_ref ) = @_;

    # blah blah
    $code_ref->({ q => $q,
                  T => \%T,
                  # etc.
                });
    # blah blah
}