From: danfinnie@...
Date: 2006-12-06T03:58:08+09:00
Subject: Re: doubt with positive lookaround

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There are a few types of "lookarounds": positive lookahead, negative lookahead, positve lookbehind, negative look behind.

To use positive lookbehind, you would use (?<=...).  Ruby might be interpreting ?=< as ?<=.  Try escaping the < by adding a \ before it.

----- Original Message -----
From: hemant 
Date: Monday, December 4, 2006 11:29 pm
Subject: doubt with positive lookaround
To: ruby-talk@ruby-lang.org (ruby-talk ML)

> I do not understand behavior of positive look arounds in Ruby:
> 
> chunked_data = "DIVex>##ECHO=b698fd4cc1ea4c7a4b5c4e1d1c402911##"
> p $& if chunked_data =~ /(?=DIVex)DI/ # => DI
> 
> However,
> 
> chunked_data = "##ECHO=b698fd4cc1ea4c7a4b5c4e1d1c402911##"
> p $& if chunked_data =~ /(?= nil
> 
> 
> does < gets treated as special character inside (?= ..) ?
> 
> 
> 
> 
> 
> 
> -- 
> There was only one Road; that it was like a great river: its springs
> were at every doorstep, and every path was its tributary.
> 
> 

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