Math::Round::Var has the following function:

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=head2 round

  $number = $rounder->round($number);

=cut
sub round {
    my $self = shift;
    my $rnd = $self->{precision};
    my $number = shift;
    return(sprintf("%0.${rnd}f", $number));
} # end subroutine round definition
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Please notice that there is neither a warning or exception if a number is not supplied. Is lack of a number argument an exception? Or should it throw a warning? Or is everything OK as it is?