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FLASH

FLASH is the FHIR-writing block syntax within the FUME language.

Use FLASH when a mapping needs to generate valid instances of FHIR resources, profiles or datatypes, and rely on FHIR-aware shaping and validation, while the expression layer computes/extracts the values that get written.

This section is a behavior-focused guide for writing and understanding FLASH mappings.

Pages​

  • Syntax: What you can type — declarations, rule forms, indentation, paths, slices, comments, semicolons.
  • Evaluation model: How a valid script evaluates — target vs input context, fan-out, append vs override, type shaping.
  • Diagnostics: How failures and warnings are reported, and how thresholds affect throwing/logging/collecting.
  • Composition and orchestration: How expression-layer orchestration and FLASH blocks compose in real mappings.
  • Examples: Curated examples that demonstrate the core features.