Quick question on trgLang

[Ryan King <ryanki@microsoft.com>]

Hi all,

 

As we’ve started implementing the standard, there are, of course, differing interpretations of some of the wording in the spec. Can the TC as a group please help me understand the following:

 

4.2.2.1 xliff

…

Constraints

·         The trgLang attribute is REQUIRED if and only if the XLIFF Document contains <target> elements that are children of <segment> or <ignorable>.

Does this constraint mean:

·         The trgLang attribute is REQUIRED if the XLIFF Document contains <target> elements that are children of <segment> or <ignorable>, otherwise it is optional.

Or does it mean:

·         The trgLang attribute is REQUIRED only if the XLIFF Document contains <target> elements that are children of <segment> or <ignorable>, otherwise it MUST not be present.

For example, is this legal?

<xliff version=”2.0” srcLang=”en-us” trgLang=”de-de”>
…
   <unit id=”1”>
      <segment id=”1”>Hello World</segment>
   </unit>

I think it is, but want to be sure I am reading this correctly. In a more general question, is there a reason why the verbiage “if and only if” is used throughout the spec and not just “if”?

Thanks,
Ryan