1 files changed, 4 insertions, 4 deletions
diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md
index 903f39994f..1a057832d4 100644
--- a/guides/source/active_support_core_extensions.md
+++ b/guides/source/active_support_core_extensions.md
@@ -1341,7 +1341,7 @@ The method `pluralize` returns the plural of its receiver:
 "equipment".pluralize # => "equipment"
 ```
 
-As the previous example shows, Active Support knows some irregular plurals and uncountable nouns. Built-in rules can be extended in `config/initializers/inflections.rb`. That file is generated by the `rails` command and has instructions in comments.
+As the previous example shows, Active Support knows some irregular plurals and uncountable nouns. Built-in rules can be extended in `config/initializers/inflections.rb`. This file is generated by default, by the `rails new` command and has instructions in comments.
 
 `pluralize` can also take an optional `count` parameter. If `count == 1` the singular form will be returned. For any other value of `count` the plural form will be returned:
 
@@ -2001,7 +2001,7 @@ Addition only assumes the elements respond to `+`:
 ```ruby
 [[1, 2], [2, 3], [3, 4]].sum    # => [1, 2, 2, 3, 3, 4]
 %w(foo bar baz).sum             # => "foobarbaz"
-{a: 1, b: 2, c: 3}.sum          # => [:b, 2, :c, 3, :a, 1]
+{a: 1, b: 2, c: 3}.sum          # => [:a, 1, :b, 2, :c, 3]
 ```
 
 The sum of an empty collection is zero by default, but this is customizable:
@@ -2789,10 +2789,10 @@ Regexp.new('.', Regexp::MULTILINE).multiline? # => true
 Rails uses this method in a single place, also in the routing code. Multiline regexps are disallowed for route requirements and this flag eases enforcing that constraint.
 
 ```ruby
-def assign_route_options(segments, defaults, requirements)
+def verify_regexp_requirements(requirements)
   ...
   if requirement.multiline?
-    raise ArgumentError, "Regexp multiline option not allowed in routing requirements: #{requirement.inspect}"
+    raise ArgumentError, "Regexp multiline option is not allowed in routing requirements: #{requirement.inspect}"
   end
   ...
 end