From: Trans <transfire@...>
Date: 2007-01-03T05:08:36+09:00
Subject: Re: Detecting default used in method calls


Eric Hodel wrote:
> No need to do those complicated things that everybody else is
> trying.  Instead use an object that nobody else will pass you as a
> sentinel:
>
> class X
>
>    SENTINEL = Object.new
>
>    def the_function(a, b = SENTINEL)
>      if b == SENTINEL then
>        ...
>      end
>    end
>
> end

You don't need to create your own, Exception works quite well:

 class X

    def the_function(a, b = Exception)
      if b == Exception then
        ...
      end
    end
 
 end

T.