It depends on the data format. Normally a variable length field is terminated by a delimiter, so a data pattern/regex is not required.
Can you describe the format in a little more detail?

regards,

Tim Kimber,
IBM Integration Bus Development (Industry Packs)
Hursley, UK
Internet:  kimbert@uk.ibm.com
Tel. 01962-816742  
Internal tel. 37246742




From:        Bing Lu <mfcplus@yahoo.com>
To:        "dfdl-wg@ogf.org" <dfdl-wg@ogf.org>,
Date:        28/03/2014 03:35
Subject:        [DFDL-WG] newbie question
Sent by:        dfdl-wg-bounces@ogf.org

---

what's the best dfdl approache to describe  a variable length alpha numeric field? should i use simpletype restriction pattern, or use dfdl:assert testPattern? thanks in advance--
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