Determining whether yields have content

rubyonrails-talk
1

Hey All, I would like some logic that would help me determine whether a yield has any content to it. For example:

<%= yield :submenu %>

I only want to display the div around the yield if the yield will have content.

Any ideas?

Thanks, Jim

2

You can do:

<% if !yield(:submenu).strip.blank? -%>    <div class="submenu">      <%= yield :submenu %>    </div> <% end -%>

The call may be expensive so you might want to create some other method of determining whether the submenu is likely to have content. But this should work.

HTH

3

Just confirming, its expensive since it renders the yield twice, correct? What if i did something like:

<% yield_contents = yield(:submenu) if !yield_contents.strip.blank? -%>

 <%= yield_contents %>

<% end -%>

Would that work?

I guess I never realized that I could yield twice. Thanks for the tip. Much appreciated.

4

That should work. A different solution altogether would be to have the submenu contain the div wrapper so you can make the test there and eliminate all the gnarly logic in your layout.