1 files changed, 6 insertions, 25 deletions
diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md
index 23736020ec..3c1bb0f132 100644
--- a/guides/source/active_support_core_extensions.md
+++ b/guides/source/active_support_core_extensions.md
@@ -422,24 +422,6 @@ NOTE: Defined in `active_support/core_ext/object/with_options.rb`.
 
 Active Support provides several methods to ease access to instance variables.
 
-#### `instance_variable_names`
-
-Ruby 1.8 and 1.9 have a method called `instance_variables` that returns the names of the defined instance variables. But they behave differently, in 1.8 it returns strings whereas in 1.9 it returns symbols. Active Support defines `instance_variable_names` as a portable way to obtain them as strings:
-
-```ruby
-class C
-  def initialize(x, y)
-    @x, @y = x, y
-  end
-end
-
-C.new(0, 1).instance_variable_names # => ["@y", "@x"]
-```
-
-WARNING: The order in which the names are returned is unspecified, and it indeed depends on the version of the interpreter.
-
-NOTE: Defined in `active_support/core_ext/object/instance_variables.rb`.
-
 #### `instance_values`
 
 The method `instance_values` returns a hash that maps instance variable names without "@" to their
@@ -920,7 +902,7 @@ When interpolated into a string, the `:to` option should become an expression th
 delegate :logger, to: :Rails
 
 # delegates to the receiver's class
-delegate :table_name, to: 'self.class'
+delegate :table_name, to: :class
 ```
 
 WARNING: If the `:prefix` option is `true` this is less generic, see below.
@@ -1449,11 +1431,10 @@ As the previous example shows, Active Support knows some irregular plurals and u
 Active Record uses this method to compute the default table name that corresponds to a model:
 
 ```ruby
-# active_record/base.rb
+# active_record/model_schema.rb
 def undecorated_table_name(class_name = base_class.name)
   table_name = class_name.to_s.demodulize.underscore
-  table_name = table_name.pluralize if pluralize_table_names
-  table_name
+  pluralize_table_names ? table_name.pluralize : table_name
 end
 ```
 
@@ -2413,9 +2394,9 @@ or yields them in turn if a block is passed:
 ```html+erb
 <% sample.in_groups_of(3) do |a, b, c| %>
   <tr>
-    <td><%=h a %></td>
-    <td><%=h b %></td>
-    <td><%=h c %></td>
+    <td><%= a %></td>
+    <td><%= b %></td>
+    <td><%= c %></td>
   </tr>
 <% end %>
 ```