From: Robert Klemme <bob.news@...>
Date: 2003-12-02T17:17:08+09:00
Subject: Re: RegExps: are they full Perl5?


"John Andrews" <john_b_andrews@yahoo.com> schrieb im Newsbeitrag
news:b64fa1e8.0312012219.6cb381ee@posting.google.com...
> How close is Ruby's Regexp support to Perl5 (say, Perl 5.6.1)?
>
> The PickAxe book covers Regexp's in maybe 15 pages (with repetition),
>  whereas "Programming Perl" 3rd edition takes on the order of 100 pages
> (I don't have my copy handy to give an exact count).
>
> I've spent some time comparing the two Regexp languages. The
> PickAxe book does not mention some operators that are in the
> Perl book.  These are so obscure that I don't know how to create
> a Ruby testcase.
>
> The reason I'm asking is that I'm giving a talk at my company
> about how Ruby compares with Perl (which we currently use), and
> I'd like to make an accurate statement about Ruby's Regexp support.

I'd say they are quite near but don't match exactly.  (Just recognizing
how well the m* word fits here... :-)))  Especially Ruby doesn't have look
behind, only look ahead: (?=...) and (?!...)

Personally I'm have only missed this feature once or twice, but not really
urgently.

Kind regards

    robert