From: Christoph <chr_news@...>
Date: 2002-03-28T01:49:33+09:00
Subject: Re: Hash.new(Hash.new) doesn't use Hash.new as default value


"ts" <decoux@moulon.inra.fr> wrote in message
news:200203271517.g2RFHfL07516@moulon.inra.fr...
> >>>>> "Y" == Yukihiro Matsumoto <matz@ruby-lang.org> writes:
>
> Y> It does not store the evaluated default value.
>
>  Yes, you are right. Sorry for the misinformation

Quoting from your and Matz's solutions back in January  (search
Google-news for `multi-dimensional Hash group:comp.lang.ruby')
you have to write this as

class MatzHash < Hash
  def default(key)
    self[key] = type.new
   # happy type-mutating;-))
  end
end

class TsHash < Hash
   def initialize
     super do |l,r| self[r] = type.new  end
     # super  do |l,r| l[r] = type.new  end
     # works too - which does not seem right too me
     # I guess Matz intended that the arguments
     # l,r take on the values key,value ...
   end
end


>
> Y>  Should it?
>
>  It depend if you want that it work like a P language (not really a good
>  reference for me :-)))

No arguments here;-))


/Christoph