From: Robert Klemme <shortcutter@...>
Date: 2009-09-19T19:00:06+09:00
Subject: Re: Newbie: Are Ruby regexp's a subset, superset, or equal to Perl's?

On 18.09.2009 21:08, Harry wrote:
> Does Ruby 1.9 explicitly support the _full_ regexp flavor of Perl
> 5.10? Specifically, things like... look-around assertions, extended /

That depends on the Ruby distribution you are using.  If you're on 1.9* 
then many of those features are supported.

> experimental Perl regexp features such as "(?{ code })"  and "(??
> { code })" .

Ruby's RX engine won't execute any code embedded in the expression 
AFAIK.  I second Fabian: look at the docs.

But one thing is sure: you cannot expect to copy a Perl regexp over to 
Ruby and use it as before, especially if advanced features are used.

<soapbox>Personally I did not have the need for embedded code in regular 
expressions yet.  If your pattern matching becomes that complex, chances 
are that a different approach (e.g. code /outside/ the rx) is better 
maintainable.  My impression is that Perl has a tendency to include more 
and more obscure features which makes it less and less readable over 
time.  When I used it on a daily basis I was pretty fluent but nowadays 
looking at Perl code gives me the creeps.</soapbox>

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/