Question

How can I display results from an object into columns like the following:

<ul>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
</ul>
<ul>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
</ul>
<ul>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
    <li><a href="#">Category name</a></li>
</ul>

Regardless of results returned to @categories = Category.all I want to divide them up into three columns like this. What’s the best way programmatically to do it?

Answer 1

each_slice method can help you

%w(a s d f g h).each_slice(3) {|x| p x}
["a", "s", "d"]
["f", "g", "h"]

In HAML, you can handle it by this way

- cats = Array.new(3, [])
  = @categories.each_slice(3) do |category|
    - cats = cats.zip(category).map(&:flatten)
  - cats.each do |subcat|
    %ul
      - subcat.each do |l|
        %li
          %a{:href => "#"}
            = l