Function: parsePq()

parsePq(el, ctx): PQ | undefined

Parse a PQ element into a typed PQ. Returns undefined when the element is absent. A non-numeric @value is preserved in raw with value omitted. Never throws.

A @nullFlavor beside a populated @value is a contradiction, and the parser resolves it against the number. <doseQuantity nullFlavor="UNK" value="10" unit="mg"/> asserts both "this quantity is unknown" and "this quantity is 10 mg". The parser emits CONTRADICTORY_NULL_FLAVOR, preserves raw ("10"), unit ("mg") and nullFlavor ("UNK") verbatim, and omits value, so med.dose.value is undefined rather than 10.

The reasoning, because the choice is not obvious and a warning alone was the alternative. A warning alone keeps the house rule (never coerce, surface verbatim, flag) but leaves the dangerous affordance intact: dose.value still hands back 10 to the many consumers who do not read warnings on a first integration, and of the two readings the reassuring one is the one that can hurt a patient. Withholding costs nothing, because value is not the document's bytes, it is a number this parser manufactured by interpreting raw, and raw is still right there. So nothing the document said is lost, and the type now forces a caller to look at what it said.

That is also exactly what MALFORMED_DATETIME already does one datatype over, TS keeps raw and drops the parsed date, so this is the existing rule applied to a second reason for not trusting an interpretation, not a new one.

The limit, stated rather than implied. Withholding applies only where a verbatim copy survives beside the derived reading, which in this model is PQ.value and TS.date and nothing else. On CD, II, ST, ED and BL the value-bearing field is the document's own text (@code, @extension, the element's content), with no second copy, so withholding it would delete what the document said rather than decline to embellish it. Those datatypes therefore warn and keep the field: a naive consumer reading allergy.allergen.code still gets the code, with nullFlavor on the same object and CONTRADICTORY_NULL_FLAVOR in warnings.

One consequence worth naming: a contradictory PQ no longer reaches MISSING_UNIT_ON_PQ (which keys off a defined value). That is not a new silence, the stronger CONTRADICTORY_NULL_FLAVOR fires in its place, and a missing unit on a value the document declared null is moot.

Parameters

el

any

ctx

ParseCtx

Returns

PQ | undefined

Example

import { parsePq } from "@cosyte/ccda";
const pq = parsePq(el, { emit: () => {} });
console.log(pq?.value, pq?.unit);