rewritten.epp

<%-
$pin = "release a=${name}" # default value
if $pin_release.length > 0
  $options = [
    if $release.length > 0         { "a=${release}" },
    if $codename.length > 0        { "n=${codename}" },
    if $release_version.length > 0 { "v=${release_version}"},
    if $component.length > 0       { "c=${component}" },
    if $originator.length > 0      { "o=${originator}" },
    if $label.length > 0           { "l=${label}" },
    ].filter |$x| { $x != undef }
  $pin = "release #{options.join(', ')}"
elsif $version.length > 0
  $pin = "version #{$version}"
elsif $origin.length > 0
  $pin = "origin #{$origin}"
end
-%>
Explanation: <%= $_explanation %>
Package: <%= $packages_string %>
Pin: <%= $pin %>
Pin-Priority: <%= $priority %>

<%-
$pin = 
  if $pin_release.length > 0 {
    { 'a' => $release,
      'n' => $codename, 
      'v' => $release_version,
      'c' => $component, 
      'o' => $originator, 
      'l' => $label
    }.filter |$assoc| { $assoc[1].length > 0 }
     .reduce([]) |$memo, $assoc | { $memo + "${assoc[0]}=${assoc[1]}" }
     .join(', ')
     .with |$options| { "release ${options}" } 
  } elsif $version.length > 0 {
    "version #{$version}"
  } elsif $origin.length > 0 {
    "origin #{$origin}"
  } else {
    "release a=${name}" # default value
  }
-%>
Explanation: <%= $_explanation %>
Package: <%= $packages_string %>
Pin: <%= $pin %>
Pin-Priority: <%= $priority %>