Added the toplevel method

Author: nobu

README.md

@@ -21,6 +21,8 @@ Or install it yourself as:
 
 ## Usage
 
+For class/module instance methods:
+
 ```ruby
 require 'ruby2_keywords'
 
@@ -30,6 +32,15 @@ module YourModule
 end
 ```
 
+For global methods:
+
+```ruby
+require 'ruby2_keywords'
+
+ruby2_keywords def oldstyle_keywords(options = {})
+end
+```
+
 ## Contributing
 
 Bug reports and pull requests are welcome on GitHub at https://bugs.ruby-lang.org.

lib/ruby2_keywords.rb

@@ -6,3 +6,10 @@ def ruby2_keywords(*)
     end
   end
 end
+
+main = TOPLEVEL_BINDING.receiver
+unless main.respond_to?(:ruby2_keywords, true)
+  def main.ruby2_keywords(*)
+    # nil
+  end
+end

ruby2_keywords.gemspec

@@ -1,4 +1,4 @@
-version = "0.0.0"
+version = "0.0.1"
 
 Gem::Specification.new do |s|
   s.name = "ruby2_keywords"