From: Avdi Grimm <avdi@...>
Date: 2007-03-20T23:09:31+09:00
Subject: Re: does Ruby not support multiple "initialize" methods for a class???

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On 3/20/07, Stefano Crocco <stefano.crocco@alice.it> wrote:
>
> You could just declare an initialize method which takes any number of
> arguments, then detect the scenario according to the passed argument. For
> example, assuming that in one case the first argument is a number and in
> the
> second is a string, you could do:
>
> class MyClass
>
> def initialize(*args)
>   if args[0].is_a? Numeric
>    #perform initialization in first case
>   elsif args[0].is_a? String
>    #perform initialization in second case
>   else raise TypeError
>   end
> end


This looks a lot nicer using "case":

class MyClass

  def initialize(*args)
    case args0
    when Numeric
      # ...perform numeric initialization
    when String
      # ...perform string initialization
    else
      raise TypeError
    end
  end

end

Of course, you can get a lot fancier with your "case" statement using
regular expressions, ranges, multiple matchers per case, etc.  The sky's the
limit...

--
Avdi

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