From: Samuel Smith <sms6395@...>
Date: 2010-04-05T23:34:50+09:00
Subject: Nested hash

Hello All.

Sample code:

class NestedHash < Hash
  attr_accessor :val
  alias :to_str :to_s
  @val=0
  def initialize
    blk = lambda {|h,k| h[k] = NestedHash.new(&blk)}
    super(&blk)
  end
  def []= (key,value)
    if value.is_a?(NestedHash)
      super(key,value)
    else
      self[key].val=value;
    end
  end
end

test=NestedHash.new();
test['1']='11'
test['1']['2']='12'
test['1']['3']='13'
test['2']['4']='24'

s=test['1'].val #s='11'

Work as expected. In C++ by using typecast overloading it is possible to
implement  class that will work that way:
s=test['1']# s='11'

Is it possible to implement same functionality in Ruby?

I've tried:

alias :to_s :to_str
def to_str
  @val
end

But first of all result values are wrong and i can't understand why.
Secondly it works only in constructions like that:
s=" "+test['1'] # ie i must tell Ruby that i need string result
but not in
s=test['1'] # if it were possible to tell Ruby that it use string result
by default

Any other suggestions?
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