Incompatible specification language for the lines element

["Robert D Anderson" <robander@us.ibm.com>]

Thanks to a customer defect report, I just noticed some seemingly incompatible rules in our spec around the <lines> element:
http://docs.oasis-open.org/dita/dita/v1.3/errata02/os/complete/part1-base/langRef/base/lines.html

The first sentence is pretty clear:
> The <lines> element contains text where line breaks are significant but white space is not.

However -- we also set a fixed attribute of xml:space="preserve", which ensures processors don't normalize those line breaks. Stating that other white space is not significant seems incompatible with the definition of xml:space in the XML specification itself:
> The value "default" signals that applications' default white-space processing modes are acceptable for this element; the value "preserve" indicates the intent that applications preserve all the white space.
https://www.w3.org/TR/xml/#sec-white-space

Based on that definition, and the fact that we don't want to break any global XML rules, I think all white space in the <lines> element has to be significant. The broader XML behavior for that attribute is definitely the behavior that my customers expected (thus the defect report).

This seems like something to address as we make progress on DITA 2.0, but I wanted to raise it to the broader TC first.

Cheers -

Robert D. Anderson
DITA-OT lead and Co-editor DITA 1.3 specification
Marketing Services Center

E-mail: robander@us.ibm.com 11501 BURNET RD,, TX, 78758-3400, AUSTIN, USA