Count Method on Undefined Active Record Array @objects.count

Is there a way to write a clean if nil then in a view. Assuming my lack of ruby is biting me here. Example,

If object nil, then return开发者_Go百科, nothing found

have

<%= @objects.count if @objects %>

want something like this

<%= @objects.count if @objects then "nothing found" %>

There are many ways to write something like this.

Something simple would be:

<% if @objects %>
  <%= @objects.count %>
<% else %>
  nothing found
<% end %>

If you get into a slightly more complex conditional I would suggest moving the logic into a helper and call it from the view. ex:

<%= count_for(@object) %>

Here's a good solution for you:

<%= "nothing found" unless @objects.try(:length).to_i > 0 %>

One of the issues is that you can't run count on a nil object. Therefore you need to use Rails' super handy .try() method to return nil when @objects = nil, rather than NoMethodError.

Next issue: You can't make a comparison between nil and a number using > so you need to convert the results of @objects.length to an integer which will return 0 for nil.

Lastly, try calling length rather than count. This will avoid running any extra queries when @objects is defined.

Avoids: SELECT COUNT(*) FROM 'objects'

Also if you want to display the count using this one-liner technique you can simply write up a shorthand if/else statement as follows:

<%= @objects.try(:length).to_i > 0 ? @objects.length : "nothing found" %>

One last option:

Use the pluralize method, which can handle a nil count:

Showing <%= pluralize( @objects.try(:length), 'object' ) %>

Sorry, I know this is pretty late, but hopefully helpful for someone else!