Sketch of ISO/IEC 30114-2 Information Technology -- Extensions of Office Open XML File Formats -- Character repertoire checking

[Shawn Villaron]

Actually there is no requirement for implementations to hold onto extLsts.  It's an optional behavior because there are cases where the implementation can ensure continued data consistency and some cases where it can't.  So we left it to the implementation to do what's right.

-----Original Message-----
From: MURATA Makoto (FAMILY Given) [mailto:eb2m-mrt at asahi-net.or.jp] 
Sent: Wednesday, August 24, 2011 6:31 AM
To: SC 34 WG4
Subject: Re: Sketch of ISO/IEC 30114-2 Information Technology -- Extensions of Office Open XML File Formats -- Character repertoire checking

I am wondering whether we should use an ignorable attribute or a child of extLst for referencing CREPDL OPC parts from SML cells.

If we use an ignorable attribute, old implementations will throw it away.
(In my understanding, ignorable attributes will be thrown away by old implemetnations silently and this is the way our spec appears to
mean.)

If we use a child of extLst, old implementations will not throw them away.  But does this approach have its own disadvantages?

Cheers,
Makoto