From: Julian Tarkhanov <listbox@...>
Date: 2007-10-01T07:14:07+09:00
Subject: Re: Detecting number ranges


On 30-sep-2007, at 23:40, Jay Levitt wrote:

> Thanks!  For my own educational purposes (and any future newbies  
> reading
> this), I renamed a bunch of variables, extracted some temp  
> variables and
> came up with the following.  It still has one bug (doesn't handle
> non-contiguous ranges like [1, 2, 133]), but I think I could fix  
> that on my
> own...

Well I used the following snippet once

  module Enumerable
    def to_ranges
      compact.sort.uniq.inject([]) do | result, elem |
        result = [elem..elem] if result.length.zero?
        if [result[-1].end, result[-1].end.succ].include?(elem)
          result[-1] = result[-1].begin..elem
        else
          result.push elem..elem
        end
        result
      end
    end

    def member_includes?(item)
      find{|r| r.include?(item)} ? true : false
    end

    def implant(item)
     (map{|e| e.to_a }.flatten + Array(item)).to_ranges
    end

    def implant!(item)
      replace(implant(item))
    end
  end

You can basically make an array and the "collapse" it

-- 
Julian 'Julik' Tarkhanov
please send all personal mail to
me at julik.nl