Type Alias: SigFieldProvenance

SigFieldProvenance = "coded" | "derived" | "absent"

Where a decoded structured-SIG field's value came from.

• "coded": the structured element carried a code (with an optional system qualifier); a SigField.code is present.
• "derived": a value was read from the structured element but it was not coded; only SigField.text is present.
• "absent": the structured element was missing or empty; neither a code nor text could be read. The field is not inferred from the free text.