<%perl>
  my @colors = qw(Red Green Blue);
  my %defaults = ( BGCOLOR => 'FFFFFF',
                   TEXT    => '000000',
                   LINK    => '0000FF',
                   ALINK   => 'FF0000',
                   VLINK   => 'AA0000',
                 );

  my @types = keys %defaults;
</%perl>

% if ( my %args = $r->content()) {
    <& rgb2hex, types => \@types, 
                colors => \@colors, 
                hex => \%defaults, 
                args => \%args &>
% } else { 
    <& form, types => \@types, 
             colors => \@colors, 
             hex => \%defaults &>
% }