Define required attributes for DescriptiveValue

[arcadiafalcone]

Such as "at least one of value, code, uri, etc" must be present.

[arcadiafalcone]

For the content of a property to be valid, it should contain at least one of the stated subproperties. If possible it would be great to get a report to find any nonconforming existing descriptive metadata.

DescriptiveValue
-value
-code
-uri
-identifier
-valueAt
-structuredValue
-parallelValue
-groupedValue

Contributor
-name
-identifier
-valueAt

Event
-date
-contributor
-location
-identifier
-note
-structuredValue

Language
-value
-code
-uri
-note
-script
-structuredValue
-parallelValue
-groupedValue
-valueAt

RelatedResource
-title
-contributor
-event
-note
-identifier
-purl
-access
-valueAt

Source
-value
-code
-uri
-note

Standard
-value
-code
-uri
-note

valueLanguage
-value
-code
-uri
-note
-valueScript

valueScript
-value
-code
-uri
-note