Processing expectations regarding the @xml:lang attribute

When the @xml:lang attribute is specified as recommended, a language for the content is clearly indicated. However, when the @xml:lang attribute is not specified, processors might need to assign a default value.

If the root element of a map or a top-level topic has no value for the @xml:lang attribute, a processor SHOULD assume a default value. The default value of the processor can be either fixed, configurable, or derived from the content itself, such as the @xml:lang attribute on the root map.

When a @conref or @conkeyref attribute is used to include content from one element into another, the processor MUST use the effective value of the @xml:lang attribute from the referenced element. If the referenced element does not have an explicit value for the @xml:lang attribute, the processor SHOULD use the default value.

Processors SHOULD render each element in a way that is appropriate for its language as identified by the @xml:lang attribute.