Merge branch 'master' of https://github.com/rails/rails into performance_test

1 files changed, 15 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/object/inclusion.rb b/activesupport/lib/active_support/core_ext/object/inclusion.rb
new file mode 100644
index 0000000000..51cfc62f2b
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/object/inclusion.rb
@@ -0,0 +1,15 @@
+class Object
+  # Returns true if this object is included in the argument. Argument must be
+  # any object which respond to +#include?+. Usage:
+  #
+  #   characters = ["Konata", "Kagami", "Tsukasa"]
+  #   "Konata".in?(characters) # => true
+  #
+  # This will throw an ArgumentError if the supplied argument doesnt not 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?")
+  end
+end