Support for Vocabulary Type

[cmoesel]

The CQL Vocabulary type represents a reference to a code system or value set, allowing either one to be passed into CQL functions.

To demonstrate how this might work, consider the following example:

library MyLibrary version '0.0.1'
valueset MyVS: 'http://example.org/vs/myvs'
codesystem MyCS: 'http://example.org/cs/mycs'
code Foo: 'Foo' from "MyCS" display 'Foo'

define function FooInVocabulary(CSorVS Vocabulary):
  if CSorVS is CodeSystem
    then Foo in (CSorVS as CodeSystem)
  else
    Foo in (CSorVS as ValueSet)

define IsFooInMyVS:
  FooInVocabulary(MyVS)

define IsFooInMyCVS:
  FooInVocabulary(MyCS)

Much like the case for ValueSet (#226) and CodeSystem (#259), the ELM representation of a function that takes a Vocabulary argument would be invoked with a ValueSetRef or CodeSystemRef.