The alternativeTitlesDomain.rng declares the 'title-role' attribute as required

[takesson]

The alternativeTitlesDomain.rng declares the 'title-role' attribute as required and with a default value. This has 2 negative side-effects:

• Editors (e.g. Oxygen) might add the 'title-role' attribute when creating an element like 'titlehint'. That's typically not necessary nor desirable.
• Trang will omit the default value when converting RNG to XSD (perhaps also to DTD). The attribute will be required but without the default value.

Declaring title-role attribute as required is inconsistent with most other attributes with a default value.

Thanks!

[raducoravu]

Editors (e.g. Oxygen) might add the 'title-role' attribute when creating an element like 'titlehint'. That's typically not necessary nor desirable.

I tested and Oxygen indeed inserts the attribute like this:

 <navtitle title-role="navigation"></navtitle>

Oxygen would not insert in general the default value of an attribute but in this case the attribute is considered required. I have not seen many situations where an attribute is considered both required and also has a default value in the schema, usually it's either one or the other.
For example if the attribute would be defined as optional in the RNG, then Oxygen would no longer feel compelled to insert it:

        <define name="navtitle.attributes">
            <optional>
                <attribute name="title-role" a:defaultValue="navigation"/>
            </optional>