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in Technique[技术] by (71.8m points)

ruby - Rails: An elegant way to display a message when there are no elements in database

I realized that I'm writing a lot of code similar to this one:

<% unless @messages.blank? %>
  <% @messages.each do |message|  %>
    <%# code or partial to display the message %>
  <% end %>
<% else %>
  You have no messages.
<% end %>

Is there any construct in Ruby and/or Rails that would let me skip that first condition? So that would be executed when iterator/loop won't enter even once? For example:

<% @messages.each do |message| %>
  <%# code or partial to display the message %>
<% and_if_it_was_blank %>
  You have no messages.
<% end %>
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0 votes
by (71.8m points)

You could also write something like this:

<% if @messages.each do |message| %>
  <%# code or partial to display the message %>
<% end.empty? %>
  You have no messages.
<% end %>

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