... and while we are at it, I noticed a different small issue with the article.

Towards the end, in the subs to_string and to_num it reads 

sub to_string {
    my $self = shift;
    return "$_->{num}/$_->{den}";
}

sub to_num {
    my $self = shift;
    return $_{num}/$_->{den};

[download]
while that should be (as it is in the cpan version 1.02) 
sub to_string {
  my $self = shift;

  return "$self->{num}/$self->{den}";
}

sub to_num {
  my $self = shift;

  return $self->{num} / $self->{den};
}

[download]

-- Hofmator

In reply to Re: if (UNIVERSAL::isa($r, ref $l)) by Hofmator
in thread if (UNIVERSAL::isa($r, ref $l)) by hossman

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