On Thursday 26 May 2011 04:22:46 jason solomon wrote:
> Say we want to write a String method called clear that takes a given
> string and modifies that string to be equal to "".
> 
> Ex.
> 
> str = "string"
> 
> we call str.clear and we get back "", not just "" printed to the screen,
> but the value of str is now "" (mutate the original string).
> 
> 
> I understand that the following code would just print "" to the screen
> but not modify the actual str object.
> 
> class String
>   def clear
>     ""
>   end
> end
> 
> 
> How would you write a method that actually modifies the str object?

This should do what you want

class String

  def clear
    replace ''
  end

end

Stefano