[ruby-talk:7302] Re: Replacing nils in arrays?

On Fri, 15 Dec 2000  07:40:01 +0900, [e-mail] wrote:
> Question for you all.
> 
> Suppose you have an array that is growing
> more or less unpredictably. You assign an
> element that is past the current end, and
> you get several new nils as a result.
> 
> My problem: I want to store zeroes, not
> nils.

quick hack:


class Array
  attr_accessor :default_value

  alias oldidx []=
  def []=(*arg)
    if arg.size == 3
      return oldidx(*arg)
    end
  
    start, elem = arg
    if start > size
      fill @default_value, size, (start - size)
    end
    oldidx start, elem
  end
end

a = [1, 2, 3]
a.default_value = 0
a[7] = 42
p a				#=> [1, 2, 3, 0, 0, 0, 0, 42]


	Michel