From: Jacob Fugal <lukfugl@...>
Date: 2005-12-22T06:14:39+09:00
Subject: Re: move to front of array

On 12/21/05, Dan Diebolt <dandiebolt@yahoo.com> wrote:
> Try this:
>
>   array1 = %w(a B c d Cool e f G)
> array1.partition {|i| i =~ /cool/i}
> array2=array1.partition {|i| i =~ /cool/i}
> array2.flatten     #or array2.flatten!

So something like:

  array = %w(a B c d Cool e f G)
  array = array.partition{ |el| el =~ /cool/i }.flatten

That certainly would work (assuming that only one element matches the
condition), and has a certain elegance. I wonder if there's a
significant performance penalty?

It also gave me this idea:

  class Array
    def bubble_up
      score = lambda{ |a| (yield a) ? -1 : 1 }
      self.sort_by { |a,b| score[a] <=> score[b] }
    end

    def bubble_up!( &proc )
      self.replace(self.bubble_up( &proc ))
    end
  end

  array = array.bubble_up! { |el| el =~ /cool/i }

Jacob Fugal