README.md in arel-helpers-2.10.0 vs README.md in arel-helpers-2.11.0

@@ -185,9 +185,35 @@
   .with_comments_by(['camertron', 'catwithtail'])
   .with_title_matching("arel rocks")
   .since_yesterday
 ```
 
+#### Conditional reflections
+
+If you have parts of a query that should only be added under certain conditions you can return `reflect(query)` from your method. E.g:
+
+```ruby
+  def with_comments_by(usernames)
+    if usernames
+      reflect(
+        query.where(post[:title].matches("%#{title}%"))
+      )
+    else
+      reflect(query)
+    end
+  end
+```
+
+This can become repetitive, and as an alternative you can choose to prepend `not_nil` to your method definition:
+
+```ruby
+  class PostQueryBuilder < ArelHelpers::QueryBuilder
+    not_nil def with_comments_by(usernames)
+      reflect(query.where(post[:title].matches("%#{title}%"))) if usernames
+    end
+  end
+```
+
 ## Requirements
 
 Requires ActiveRecord >= 3.1.0, < 6, tested against Ruby 2.2.4. Depends on SQLite for testing purposes.
 
 ## Running Tests