<h1>Compare Stackage snapshots

<div .container .content>
  <div .packages>
    <table .table>
      <thead>
        <th>
          <select .form-control onchange="document.location = this.value">
            <optgroup label="LTS">
              $forall name1' <- ltsSnaps
                $if name1' == name1
                  <option selected value=@{StackageDiffR name1' name2}>#{toPathPiece name1'}
                $else
                  <option value=@{StackageDiffR name1' name2}>#{toPathPiece name1'}
            <optgroup label="Nightly">
              $forall name1' <- nightlySnaps
                $if name1' == name1
                  <option selected value=@{StackageDiffR name1' name2}>#{toPathPiece name1'}
                $else
                  <option value=@{StackageDiffR name1' name2}>#{toPathPiece name1'}
        <th>
          <select .form-control onchange="document.location = this.value">
            <optgroup label="LTS">
              $forall name2' <- ltsSnaps
                $if name2' == name2
                  <option selected value=@{StackageDiffR name1 name2'}>#{toPathPiece name2'}
                $else
                  <option value=@{StackageDiffR name1 name2'}>#{toPathPiece name2'}
            <optgroup label="Nightly">
              $forall name2' <- nightlySnaps
                $if name2' == name2
                  <option selected value=@{StackageDiffR name1 name2'}>#{toPathPiece name2'}
                $else
                  <option value=@{StackageDiffR name1 name2'}>#{toPathPiece name2'}
      <tbody>
        $forall (pkgname, VersionChange verChange) <- toDiffList snapDiff
          <tr>
            $case verChange
              $of This oldVersion
                <td>
                  <a href=@{packageUrl name1 pkgname oldVersion}#changes}>
                    #{pkgname}-#{oldVersion}
                <td>
              $of That newVersion
                <td>
                <td>
                  <a href=@{packageUrl name2 pkgname newVersion}#changes>
                    #{pkgname}-#{newVersion}
              $of These oldVersion newVersion
                <td>
                  <a href=@{packageUrl name1 pkgname oldVersion}#changes>
                    #{pkgname}-#{oldVersion}
                <td>
                  <a href=@{packageUrl name2 pkgname newVersion}#changes>
                    #{pkgname}-#{newVersion}
