From: "Brian F. Feldman" <green@...>
Date: 2001-10-24T04:10:34+09:00
Subject: [ruby-talk:23073] Re: splitting a string with nested elements

Robert Feldt <feldt@ce.chalmers.se> wrote:
> On Wed, 24 Oct 2001, Joseph McDonald wrote:
> 
> > Hi,
> > 
> Hi,
> 
> > Is there a way to do such a thing with a regex, or do I need to resort
> > to a scanning technique, keeping track of the nested elements?
> > 
> Nested comments is the canonical example of what can *NOT* be done with
> regexps. But since I now said this I'm sure some smart ruby guru will tell
> you it can be done anyway (I'm not fully aware of the difference between
> RegularExpressions (the CS theory one) and their Perl and Ruby
> implementations). 
> 
> BTW, the an upcoming version of Rockit will have an expanded
> tokenizing/lexing/scanning formalism that can easily handle this.

Writing a recursive-descent parser using regexes for string matching is a 
quite simple thing to do.  So though a single regex alone plus Regexp#scan 
isn't enough, you can still do it in one method without major trouble :)


-- 
 Brian Fundakowski Feldman           \  FreeBSD: The Power to Serve!  /
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