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Expression

Base StructureDefinition for Expression Type: A expression that is evaluated in a specified context and returns a value. The context of use of the expression must specify the context in which the expression is evaluated, and how the result of the expression is used.

Properties

NameRequiredTypeDescription
idstring

Unique id for inter-element referencing

Details

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

extensionExtension[]

Additional content defined by implementations

Details

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

descriptionstring

Natural language description of the condition

Details

A brief, natural language description of the condition that effectively communicates the intended semantics.

nameid

Short name assigned to expression for reuse

Details

A short name assigned to the expression to allow for multiple reuse of the expression in the context where it is defined.

languagecode

text/cql | text/fhirpath | application/x-fhir-query | etc.

Details

The media type of the language for the expression.

expressionstring

Expression in specified language

Details

An expression in the specified language that returns a value.

referenceuri

Where the expression is found

Details

A URI that defines where the expression is found.

If both a reference and an expression is found, the reference SHALL point to the same expression.