A VS Code extension that adds hover info, code lenses, diagnostics, and autocomplete for HL7 v2 messages in Rhapsody/HAPI JavaScript code.
Features
Hover tooltips
Hover over a segment, field, or component index to get the definition of that component. Shows segment/field/component names and datatypes.
IntelliSense Suggestions
Auto complete suggestions as you type.
Autocomplete
Segments (PID, PV1, …)
Fields (with labels and datatypes)
Components (with labels)
Suggestions pop when typing and when moving the cursor into a slot.
Numeric items are sorted correctly (1, 2, 3, … not 1, 10, 11).
Selecting an item replaces the token you’re on.
Replace field suggestions
Placing the cursor into a field that already contains a value will trigger IntelliSense and selection will replace the existing value.
CodeLens shortcuts
Links above calls to open official HL7 segment/datatype documentation.
Diagnostics
Invalid field/component numbers are squiggled with a warning.
Usage
In JavaScript/TypeScript files that use Rhapsody/HAPI-style calls:
msg.getValue("PID", 0, 3, 0, 1, 1)
Place the cursor on "PID" → autocomplete segments.
Place the cursor on 3 → autocomplete PID fields.
Place the cursor on 1 (component) → autocomplete CX components.
Supports both:
msg.getValue(...) (member form)
hl7.getValue(msg, ...) (wrapper form)
Multi-line calls.
Settings
Extension contributes these settings:
hl7Helper.fnNames: Functions to match (default: ["getValue","setValue","getValues","setValues"])
hl7Helper.version: HL7 version (v231, v240, v251, v27)
hl7Helper.specBaseUrl: Base URL for documentation links (default: Caristix HL7 spec)
Development
Compile: npm run compile
Watch mode: npm run watch
Debug: F5 in VS Code → Extension Development Host
Package:
npx vsce package
Known quirks
Path-style calls ("/PID(0)-3(0)-1(1)") have hover support, completions are basic.
Field/component completions always show the full list (even if a digit is present) by design.
The Future
Setting: hl7Helper.debug (boolean) to enable logs.
Command: “HL7: Reload Dictionaries” (re-reads JSON without reload).
Unit tests for parsing (getEffIndexAtPosition, partial-arg reader).
Path-style completions ("/PID(0)-3(0)-1(1)") like you did for index style.
Go to definition-ish command that navigates to the spec of the hovered item directly (segment/field/component).
Caching: memorize parsed JSON for perf on huge workspaces.
