anchor.diff:                              td(class=(column._id.toString() == columns[index]._id.toString() ? "selected-column" : ""))
                                   a(href="/columns/" + columns[index]._id)
                                       strong= columns[index].name
  -                    tr
  -                        td.text-center
  -                            a.button.button-primary.button-pill.button-small(href="/columns/new") 添加专栏
  +                    if current_user
  +                        tr
  +                            td.text-center
  +                                a.button.button-primary.button-pill.button-small(href="/columns/new") 添加专栏
               .col-lg-8.col-md-8.col-sm-8
                   .box.box-solid
                       .box-header.with-border
  
positive.code:                         else
                              h4
                                  strong 该专栏下还没有文章
                      .box-footer.text-center
                          a.button.button-primary.button-pill(href="/columns/" + column._id + '/articles/new') 添加专栏文章
      include ./reference
negative.code:                             h3
                                  i.fa.fa-book
                                  strong.margin= column.name
                          if current_user
                              a.pull-right.btn.btn-app(href="/columns/" + column._id + '/edit')
                                  i.fa.fa-pencil
                                  | 修改
                              a.pull-right.btn.btn-app(href="/columns/" + column._id + "?_method=DELETE" style="margin-left: 10px;")
                                  i.fa.fa-trash
                                  | 删除
                      .box-body
                          #column-introduction= global.utils.markdown(column.introduction)
                      .box-body
  