diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md
index de42f13145..f6f96b79c6 100644
--- a/guides/source/active_support_core_extensions.md
+++ b/guides/source/active_support_core_extensions.md
@@ -1833,16 +1833,14 @@ attribute names:
 
 ```ruby
 def full_messages
-  full_messages = []
+  map { |attribute, message| full_message(attribute, message) }
+end
 
-  each do |attribute, messages|
-    ...
-    attr_name = attribute.to_s.gsub('.', '_').humanize
-    attr_name = @base.class.human_attribute_name(attribute, default: attr_name)
-    ...
-  end
-
-  full_messages
+def full_message
+  ...
+  attr_name = attribute.to_s.tr('.', '_').humanize
+  attr_name = @base.class.human_attribute_name(attribute, default: attr_name)
+  ...
 end
 ```