From: Andrew Johnson <ajohnson@...>
Date: 2006-02-04T07:03:19+09:00
Subject: Re: Regexp question for doing "and" searches

On Sat, 4 Feb 2006 06:38:12 +0900, Jeff Cohen <cohen.jeff@gmail.com> wrote:
> Just can't quite figure this one out.
> 
> Given a search phrase like "one two three", I want to search a list of 
> text strings for onex that contain ALL of those words, but not 
> necessarily in that order.

You can use look-aheads to build a re that looks like:
  
  /^(?=.*\bone\b)(?=.*\btwo\b)(?=.*\bthree\b)/

ensuring a match only if all look-ahead assertions pass.

  phrase = "one two three"
  re = %r/^#{phrase.split.map{|s|"(?=.*\\b#{s}\\b)"}}/
  while DATA.gets
    print if ~re
  end
  __END__
  one two three YUP
  one three two YUP
  zone two three NOPE
  three and two and one YUP

regards,
andrew