1 files changed, 14 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/name_error.rb b/activesupport/lib/active_support/core_ext/name_error.rb
index e1ebd4f91c..b82148e4e5 100644
--- a/activesupport/lib/active_support/core_ext/name_error.rb
+++ b/activesupport/lib/active_support/core_ext/name_error.rb
@@ -1,5 +1,12 @@
 class NameError
   # Extract the name of the missing constant from the exception message.
+  #
+  #   begin
+  #     HelloWorld
+  #   rescue NameError => e
+  #     e.missing_name
+  #   end
+  #   # => "HelloWorld"
   def missing_name
     if /undefined local variable or method/ !~ message
       $1 if /((::)?([A-Z]\w*)(::[A-Z]\w*)*)$/ =~ message
@@ -7,6 +14,13 @@ class NameError
   end
 
   # Was this exception raised because the given name was missing?
+  #
+  #   begin
+  #     HelloWorld
+  #   rescue NameError => e
+  #     e.missing_name?("HelloWorld")
+  #   end
+  #   # => true
   def missing_name?(name)
     if name.is_a? Symbol
       last_name = (missing_name || '').split('::').last