From: bwv549 <jtprince@...>
Date: 2007-07-24T06:29:59+09:00
Subject: Re: finding positions in a string

> require 'enumerator'
> def substring_positions(substring, string)
>    string.enum_for(:scan, substring).map { $~.offset(0)[0] }
> end

That's the one-line magic I knew was hiding out there.  I will use it
and see if it is acceptably fast.  Thanks