lib/mir_extensions.rb
def tag_for_collapsible_row(obj, params)
      _html = ""
      if obj && obj.respond_to?(:parent) && obj.parent
        _html << %{<tr class="#{obj.class.name.downcase}_#{obj.parent.id} #{params[:class]}" style="display: none; #{params[:style]}">}
      else
        _html << %{<tr class="#{params[:class]}" style="#{params[:style]}">}
      end
      _html
    end
def tag_for_collapsible_row(obj, params)
      _html = ""
      if obj && obj.respond_to?(:parent) && obj.parent
        _html << %{<tr class="#{obj.class.name.downcase}_#{obj.parent.id} #{params[:class]}" style="display: none; #{params[:style]}">}
      else
        _html << %{<tr class="#{params[:class]}" style="#{params[:style]}">}
      end
      _html
    end
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