sub max_columns{
    my ($self,$value) = @_;
    
    $self->{max_cols} = $value if defined $value and $value =~ /^[1-9]\d*$/;
    
    my $caller = (caller(1))[3];
    unless( ($caller and $caller =~ /min_columns/) or not defined $self->min_columns){
        $self->min_columns($self->{max_cols}) if $self->{max_cols} < $self->min_columns;
    }
    
    return $self->{max_cols};
}

=head2 min_columns

set how many columns the table can have (at least).

    $tabulator->min_columns(3);

the table has at least three columns

=cut

sub min_columns{
    my ($self,$value) = @_;
    
    $self->{min_cols} = $value if defined $value and $value =~ /^[1-9]\d*$/;
    
    my $caller = (caller(1))[3];
    unless( $caller and $caller =~ /max_columns/){
        $self->max_columns($self->{min_cols}) if $self->{min_cols} > $self->max_columns;
    }
    
    return $self->{min_cols};
}