SystemVersionProcessingMode

How to manage the intersection between a fixed version in a value set, and a fixed version of the system in the expansion profile

This code system http://hl7.org/fhir/system-version-processing-mode defines the following codes:

Code	Display	Definition
default	Default Version	Use this version of the code system if a value set doesn't specify a version
check	Check ValueSet Version	Use this version of the code system. If a value set specifies a different version, the expansion operation should fail
override	Override ValueSet Version	Use this version of the code system irrespective of which version is specified by a value set. Note that this has obvious safety issues, in that it may result in a value set expansion giving a different list of codes that is both wrong and unsafe, and implementers should only use this capability reluctantly. It primarily exists to deal with situations where specifications have fallen into decay as time passes. If a version is override, the version used SHALL explicitly be represented in the expansion parameters