Question

I have 2 instance objects : @original_files and @version2_files

I want to retrieve the elements found in @original_files but NOT FOUND in @version2_files.

The code below:

<% @original_files.each do |original_file| %>

  <% @version2_files.each do |ver2_file| %>
    <% if original_file.name ==  ver2_file.name%>
      <%= original_file.name %> is common to both sets
      <% break %>
      <% else %>
    <% end %>
  <% end %>

<% end %>

I would appreciate it if someone could help me figure out how to find the elements found in @original_files only.

Thanks

Answer 1

They are arrays? You can subtract…

@original_files - @version2_files

Hashes can use diff.

 @original_files.diff(@version2_files)