Attached with my comments.

From: dfdl-wg-bounces@ogf.org [mailto:dfdl-wg-bounces@ogf.org] On Behalf Of Alan Powell
Sent: Thursday, April 02, 2009 12:06 PM
To: dfdl-wg@ogf.org
Subject: [DFDL-WG] Simplified EscapeScheme proposal

While working through the previous generalized proposal for escape schemes it became obvious that it was becoming overly complicated for what are believed to be a small number of escaping mechanisms. It had become particularly difficult to define the rules for when escaping should be used 'when needed'

The attached proposal is much simplified and covers just three variants of escaping mechanisms.

- The use of a single escape character to cause the next character to be interpreted literally. The escape character itself is escaped by the escape escape character.

- The use of a pair of escape strings to cause the enclosed group of characters to be interpreted literally. The ending escape string is escaped by an escape escape character.

- The use of a pair of escape strings to cause the enclosed group of characters to be interpreted literally. An alternate pair of escape strings is used when the data contains the first ending escape string.

I have also introduced an extraEscapedCharacters property which is a list of additional single characters which must be escaped as a get out for other mechanisms

Alan Powell

MP 211, IBM UK Labs, Hursley, Winchester, SO21 2JN, England
Notes Id: Alan Powell/UK/IBM email: alan_powell@uk.ibm.com
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