sub import {
    # two loops because we don't want to splice @_ while looping over it
    if ( grep { /:(?:bar|baz)/ } @_ ) {
        my $sub = caller(0) . '::set';
        {
            no strict 'refs';
            *{$sub} = \&set;
        }
    }
    # using goto to avoid updating caller
    goto &Foo::import;
}