scales.xml
Creates OptionalDslBuilder instances. If none of the end Elems contain data (either attributes or child text nodes) the result of the builder is None.
Creates a OptionalDslBuilder with the given elem as root
Creates an OptionalDslBuilder with qname as the root Elems
Creates OptionalDslBuilder instances. If none of the end Elems contain data (either attributes or child text nodes) the result of the builder is None.