Date:         Mon, 19 Jun 2006 10:53:59 -0600
Reply-To:     Alan Churchill <SASL001@SAVIAN.NET>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Alan Churchill <SASL001@SAVIAN.NET>
Subject:      Do regular expressions need to be declared in _n_=1
Content-Type: text/plain; charset="iso-8859-1"

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