Extension Methods and IronRuby

You may or may not be excited about C# getting extension methods but this idea is a core part of Ruby. IronRuby carries this spirit into .NET where it's a simple matter to add a method to an existing class--even a BCL class.

As rich as the BCL classes are, there are times where a bit of functionality is just plain missing. In sticking with true object-oriented practices, Ruby makes it easy to add that functionality where it belongs.

Suppose that you are constantly turning your strings into questions. Instead of creating a Questionizer class that takes a string and manipulates it in some way, wouldn't it be nice to just store our questionizing functionality on the strings themselves? Enter the IronRuby prompt and type the following:

>>> class String
...   def questionize
...     self + ", eh?"
...   end
... end
=> nil

You just added a method to all String objects. Now you can use your method anywhere that you have a string object:

>>> "Nice weather".questionize
=> "Nice weather, eh?"

Now go forth and put your functionality where it clearly belongs!