From: Austin Ziegler <austin@...>
Date: 2003-11-15T23:58:55+09:00
Subject: Re: substring: to the end of the string

On Sat, 15 Nov 2003 10:24:42 +0900, Bermejo, Rodrigo wrote:
> class String
>   def substring
>     /(^...)(.*)\z/ =~ self
>     return $2
>   end
> end

As Gavin pointed out, regexen are overkill here. However, the
technique is worth noting:

class String
  def substring(start, len = nil)
    if len.nil?
      /^.{#{start}}(.*)/m =~ self
    else
      /^.{#{start}}(.{#{len}})/m =~ self
    end
    $1
  end
end

  "123456".substring(3)     # => "456"
  "123456".substring(3, 2)  # => "45"

-austin
--
austin ziegler    * austin@halostatue.ca * Toronto, ON, Canada
software designer * pragmatic programmer * 2003.11.15
                                         * 09.51.26