Date:         Mon, 19 Jun 2006 11:19:25 -0600
Reply-To:     Alan Churchill <SASL001@SAVIAN.NET>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Alan Churchill <SASL001@SAVIAN.NET>
Subject:      Re: Do regular expressions need to be declared in _n_=1
Comments: To: "Choate, Paul@DDS" <pchoate@DDS.CA.GOV>
In-Reply-To:  <A4F0DBF1F84D4F46A0E6D56405D3511989E242@HHAEXMB03.rf01.itservices.ca.gov>
Content-Type: text/plain; charset="us-ascii"

Thanks Paul.

The examples show the use of _n_=1 but I thought that the speaker there said
this was changed in version 9 so that it wouldn't be necessary. All the
examples show the use of _n_=1 which I would expect. However, I seem to
recall specifically that they said it wouldn't be needed.

The question I have is whether it is necessary and, if not, what version of
SAS were they referring to? 9.13 or 9.2?

Alan

Alan Churchill
Savian "Bridging SAS and Microsoft Technologies"
www.savian.net


-----Original Message-----
From: Choate, Paul@DDS [mailto:pchoate@DDS.CA.GOV]
Sent: Monday, June 19, 2006 11:10 AM
To: Alan Churchill; SAS-L@LISTSERV.UGA.EDU
Subject: RE: Do regular expressions need to be declared in _n_=1

The search and extract section of the tip sheet confirm this:

http://support.sas.com/rnd/base/topics/datastep/perl_regexp/regexp-tip-s
heet.pdf


as do the examples here:

http://support.sas.com/rnd/base/topics/datastep/perl_regexp/regexp.motiv
ation.html#Examples


hth

Paul Choate
DDS Data Extraction
(916) 654-2160

> -----Original Message-----
> From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of
Alan
> Churchill
> Sent: Monday, June 19, 2006 9:54 AM
> To: SAS-L@LISTSERV.UGA.EDU
> Subject: Do regular expressions need to be declared in _n_=1
>
> All,
>
> I seem to recall at the last SUGI that regular expression patterns are
> automatically retained and are only processed once in a data step. For
> example,
>
> Old Way:
>
> Data test ;
>        Infile 'something or other' ;
>        Input;
>        Retain pattern ;
>        If _n_ = 1 then
>            Do ;
>                  Pattern = prxparse("/some regex/") ;
>            End;
> Run ;
>
>
> Optional way:
>
> Data test ;
>        Infile 'something or other' ;
>        Input;
>        Pattern = prxparse("/some regex/") ; Run ;
>
>
> Can anyone confirm this?
>
> Thanks,
> Alan
>
> Alan Churchill
> Savian "Bridging SAS and Microsoft Technologies"
> www.savian.net