Lazy-require builder lib

activesupport/lib/active_support/core_ext/array/conversions.rb

-require 'builder'
-
 module ActiveSupport #:nodoc:
   module CoreExtensions #:nodoc:
     module Array #:nodoc:
@@ -149,6 +147,7 @@ def to_formatted_s(format = :default)
         #
         def to_xml(options = {})
           raise "Not all elements respond to to_xml" unless all? { |e| e.respond_to? :to_xml }
+          require 'builder' unless defined?(Builder)
 
           options[:root]     ||= all? { |e| e.is_a?(first.class) && first.class.to_s != "Hash" } ? first.class.to_s.underscore.pluralize : "records"
           options[:children] ||= options[:root].singularize

activesupport/lib/active_support/core_ext/hash/conversions.rb

 require 'date'
 require 'cgi'
-require 'builder'
 require 'xmlsimple'
 
 # Locked down XmlSimple#xml_in_string
@@ -113,6 +112,8 @@ def to_query(namespace = nil)
         alias_method :to_param, :to_query
 
         def to_xml(options = {})
+          require 'builder' unless defined?(Builder)
+
           options[:indent] ||= 2
           options.reverse_merge!({ :builder => Builder::XmlMarkup.new(:indent => options[:indent]),
                                    :root => "hash" })