Pathling leverages the FHIRPath language in order to abstract away some of the complexity of navigating and interacting with FHIR data structures.
FHIRPath is actually a model-independent language at its core. For this reason, the FHIRPath language is defined in two places:
- The core FHIRPath specification, and;
- The FHIRPath page within the FHIR R4 specification, which binds FHIRPath to FHIR and defines some FHIR-specific functions and behaviour.
The data types, functions and operators supported by Pathling are described in this document, with links back to the relevant sections of the FHIRPath specifications.
For convenience, this document does contain some redundant information copied from the source specification. Where there are variations from the specification, this document describes the behaviour as implemented within Pathling.
The following sections from the FHIRPath specification are recommended reading: