Review #2 comments: Processing key references

[Kristen James Eberlein <kris@eberleinconsulting.com>]

DITAweb URL:
https://ditaweb.com/oasis-dita/#/00074601-DA$00074010-DB$Processing%20key%20references

Text in question:
"he effective key definitions for a key space might be affected by conditional processing (filtering). Processors must perform conditional processing before determining the effective definition for a key reference. However, processors might determine key space contents before filtering. Consequently, different processors might produce different effective bindings for the same map when there are key definitions that might be filtered out based on their filtering attributes."

Comment from Eliot:
"This paragraph is absolutely wrong.

It cannot be the case that filtering would result in different effective key definitions. 

There are two processing possibilities:

1. Filtering is applied to the map before key space construction

2. Filtering is applied to the *key space* after key space construction

In both cases, the result of filtering MUST be the same (that is, the spec must require that you get the same result).

In case 1 the processing is obvious: only those key definitions that remain after filtering are considered.

In case 2, the key space, as constructed must maintain both the original precedence order of the key definitions and the conditions to which each key definition applied.

When keys are resolved in the context of a case-2 key space, the active filtering conditions must be used and thus *exactly the same key definition* will be selected as in case 1.

Therefore the key resolution result will always be the same for the same input map and active filtering conditions.

This is what 1.2 said and it must continue to be true.

Response from Robert Anderson:
"DITA 1.2 language is very similar to what we have here: "The effective keys for a map might be affected by conditional processing (filtering). Processors should perform conditional processing before determining effective key definitions. However, processors may determine effective key bindings before filtering. Consequently, different processors might produce different effective bindings for the same map when there are key definitions that might be filtered out based on their select attributes."

Referring to TC for follow-up."

--
Best,
Kris

Kristen James Eberlein
Chair, OASIS DITA Technical Committee
Principal consultant, Eberlein Consulting
www.eberleinconsulting.com
+1 919 682-2290; kriseberlein (skype)