1 files changed, 19 insertions, 9 deletions
diff --git a/activesupport/lib/active_support/core_ext/object/inclusion.rb b/activesupport/lib/active_support/core_ext/object/inclusion.rb
index b5671f66d0..3fec465ec0 100644
--- a/activesupport/lib/active_support/core_ext/object/inclusion.rb
+++ b/activesupport/lib/active_support/core_ext/object/inclusion.rb
@@ -1,15 +1,25 @@
 class Object
-  # Returns true if this object is included in the argument. Argument must be
-  # any object which responds to +#include?+. Usage:
+  # Returns true if this object is included in the argument(s). Argument must be
+  # any object which responds to +#include?+ or optionally, multiple arguments can be passed in. Usage:
   #
-  #   characters = ["Konata", "Kagami", "Tsukasa"]
-  #   "Konata".in?(characters) # => true
+  #   characters = ['Konata', 'Kagami', 'Tsukasa']
+  #   'Konata'.in?(characters) # => true
   #
-  # This will throw an ArgumentError if the argument doesn't respond
+  #   character = 'Konata'
+  #   character.in?('Konata', 'Kagami', 'Tsukasa') # => true
+  #
+  # This will throw an ArgumentError if a single argument is passed in and it doesn't respond
   # to +#include?+.
-  def in?(another_object)
-    another_object.include?(self)
-  rescue NoMethodError
-    raise ArgumentError.new("The parameter passed to #in? must respond to #include?")
+  def in?(*args)
+    if args.length > 1
+      args.include? self
+    else
+      another_object = args.first
+      if another_object.respond_to? :include?
+        another_object.include? self
+      else
+        raise ArgumentError.new 'The single parameter passed to #in? must respond to #include?'
+      end
+    end
   end
 end