Just to give you an idea, here's a little trick i like to use when i need to process 1 or more items. If the argument is a scalar, then wrap it in an array ref:

sub some_func {
    my ($args) = @_;    

    # if $args is a scalar, then make it an array ref
    $args = [$args] unless ref $args eq 'ARRAY';

    # now process 
    foreach my $arg (@$args) {
        # do stuff
    }
}

# sample calls:
some_func($one_item);
some_func([qw(bunch of items)]);
[download]

From there it is a piece of cake to pass multiples of these in the hash construct that you showed:

some_func({
    this => $one_item,
    that => [$some, $more, $items],
});
[download]

Hope this helps. :)

Jeff

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