From: Payton Swick <payton@...>
Date: 2005-12-22T23:56:09+09:00
Subject: Re: move to front of array

Just for the sake of completeness, here is Devin's suggestion, with 
syntax errors corrected:

class Array
   def bubble_if!(regex=nil)
     if block_given? then each_with_index {|o,i| unshift(delete_at(i)) 
if yield o}
     else bubble_if! {|o| o =~ regex}
     end
   end
end

Thanks for the suggestions, everyone!

-Payton

Devin Mullins wrote:
> Payton Swick wrote:
> 
>> Hi,
>>
>> I have an array of Strings, and I'd like to find one of the items by 
>> Regexp, then move that item to the front of the array, eg:
>>
>> array = %w(a B c d Cool e f G)
>> array.unshift(array.slice!(array.index(array.find { |i| i =~ /cool/i 
>> }))) if array.find { |i| i =~ /cool/i }
>>
>> Better/cleaner/shorter ways to do it?
> 
> 
> I'm going to do something controversial and suggestion a completely 
> imperative method:
> 
> array.each_with_index {|o,i| array.unshift(array.delete_at(i)) if o =~ 
> /cool/i}
> 
> Oddly, this works with multiple instances of Cool. I take it that 
> #each_with_index doesn't miss a beat wrt the modifications.
> 
> Oh, and if you'll be doing it more than once in your code, then put the 
> method where it belongs:
> class Array
> def bubble_if!(regex=nil)
>  if block_given? then each_with_index {|o,i| unshift(delete_at(i)) if 
> yield o}
>  else super() {|o| =~ regex}
>  end
> end
> end
> array.bubble_if!(/cool/i)
> 
> Devin
> YMMV.
>