From: James Edward Gray II <james@...>
Date: 2005-09-26T06:42:09+09:00
Subject: Re: String#ggsub

On Sep 25, 2005, at 3:25 PM, Gavin Kistner wrote:

> I occasionally find myself with gsub regexp that either eat too  
> much, or work within a nesting, such that I need to run gsub more  
> than once in order to get the desired end result. The code I end up  
> writing tends to be of the form:
>
> while foo.gsub!( /.../, ... ); end
>
> Frankly, I really don't like that. It's like JS people who write  
> things like:
> for ( var walkerNode = this; walkerNode.parent; walkerNode =  
> walkerNode.parent ){}
> 'abusing' the for loop construct to hold their logic.
>
> Is there some other form in Ruby of "keep doing this until it  
> returns nil" that is less...gross?

Of course, it's trivial to roll one up:

#!/usr/local/bin/ruby -w

module Kernel
     def complete
         loop { break unless yield }
     end
end

if __FILE__ == $0
     digits = "3211"
     complete { digits.gsub!(/(\d)\1+/) { |d| d[0, 1].to_i + 1 } }
     p digits    # => "4"
end

__END__

Though I do realize that's not what you asked.

James Edward Gray II