Support item initial

Author: olimsaidov

README.md

@@ -41,24 +41,24 @@ Each milestone lists the core features and extensions required to reach full com
 Focus: Establish baseline FHIR Questionnaire support and base rendering logic.
 
 * [ ] **Core Questionnaire Resource**
-    * [ ] Support `Questionnaire.item` elements (text, type, linkId, required, repeats)
-    * [ ] Implement display of `prefix`, `text`, `item.type`
+    * [x] Support `Questionnaire.item` elements (text, type, linkId, required, repeats)
+    * [x] Implement display of `prefix`, `text`, `item.type`
     * [ ] Apply constraints: `minLength`, `maxLength`, `minValue`, `maxValue`, `maxOccurs`
-    * [ ] Enable `readOnly`, `initial`, and `defaultValue` behavior
-    * [ ] Support FHIR `enableWhen` conditions and nested groups
+    * [x] Enable `readOnly`, `initial` behavior
+    * [x] Support FHIR `enableWhen` conditions and nested groups
     * [ ] Render `item.control` and `item.control.displayCategory` extensions (basic)
-* [ ] **Questionnaire Navigation & Layout**
-    * [ ] Implement group hierarchy rendering
+* [ ] **Questionnaire Navigation & Layout*_*_
+    * [x] Implement group hierarchy rendering
     * [ ] Respect `hidden` and `displayCategory` controls
     * [ ] Add label localization and prefix rendering
 * [ ] **Input Controls**
-    * [ ] Map FHIR types → UI components (`string`, `boolean`, `integer`, `choice`, `date`, `quantity`, etc.)
+    * [x] Map FHIR types → UI components (`string`, `boolean`, `integer`, `choice`, `date`, `quantity`, etc.)
     * [ ] Render choice options (`answerOption`, `answerValueSet`)
     * [ ] Support open-choice types
 * [ ] **Basic Validation**
-    * [ ] Validate required questions
-    * [ ] Validate numeric and string bounds
-    * [ ] Validate answer cardinality (`repeats`, `maxOccurs`)
+    * [x] Validate required questions
+    * [x] Validate numeric and string bounds
+    * [x] Validate answer cardinality (`repeats`, `maxOccurs`)
 
 ## ⚙️ **November 2025 — Advanced Form Rendering & Behavior**
 
@@ -69,8 +69,8 @@ Focus: Interactive logic, calculations, adaptive elements, and modular assembly.
     * [ ] Handle `appearance` extension rendering hints
     * [ ] Support `rendering-style`, `rendering-xhtml`, and `markdown` items
 * [ ] **Form Behavior & Calculation**
-    * [ ] Implement calculated expressions via `calculatedExpression`
-    * [ ] Dynamic enablement: `enableWhenExpression`
+    * [x] Implement calculated expressions via `calculatedExpression`
+    * [x] Dynamic enablement: `enableWhenExpression`
     * [ ] Validation expressions: `constraint`, `constraintExpression`
     * [ ] Item visibility & computed display expressions
     * [ ] Value propagation (`derivedFrom`, `answerExpression`)
@@ -81,16 +81,16 @@ Focus: Interactive logic, calculations, adaptive elements, and modular assembly.
     * [ ] Support inclusion of external subforms and library dependencies
 * [ ] **User Interaction Layer**
     * [ ] Autosave progress to `QuestionnaireResponse`
-    * [ ] Support for resuming saved sessions
-    * [ ] Dynamic updates to visible fields based on answers
+    * [x] Support for resuming saved sessions
+    * [x] Dynamic updates to visible fields based on answers
 
 ## 🧩 **December 2025 — Data Population & Extraction**
 
 Focus: Form prefill, structured output mapping, and integration services.
 
 * [ ] **Form Population**
     * [ ] Implement population via:
-        * [ ] `initialExpression`
+        * [x] `initialExpression`
         * [ ] `itemPopulationContext`
         * [ ] `candidateExpression`
     * [ ] Support FHIR `$populate` operation (StructureMap-based)
@@ -100,7 +100,7 @@ Focus: Form prefill, structured output mapping, and integration services.
     * [ ] Map responses → resources using `structureMap`
     * [ ] Handle `extract` extensions: `sdc-questionnaire-extract`, `itemExtractionContext`
 * [ ] **Export and Serialization**
-    * [ ] Generate valid `QuestionnaireResponse`
+    * [x] Generate valid `QuestionnaireResponse`
     * [ ] Support export in JSON and XML
     * [ ] Validate `QuestionnaireResponse` against source `Questionnaire`
 * [ ] **Polish & QA**

demo/app.tsx

@@ -124,9 +124,9 @@ export function App() {
 
   const sampleOptions = useMemo(
     () =>
-      demoSamples.map((sample) => ({
+      demoSamples.map((sample, index) => ({
         id: sample.id,
-        label: sample.label,
+        label: `${index + 1}. ${sample.label}`,
       })),
     [],
   );

demo/samples/index.ts

@@ -6,6 +6,7 @@ import numericThresholds from "./numeric-thresholds.json" assert { type: "json"
 import repeatingQuestion from "./repeating-question.json" assert { type: "json" };
 import repeatingGroup from "./repeating-group.json" assert { type: "json" };
 import nestedFollowUps from "./nested-follow-ups.json" assert { type: "json" };
+import staticInitials from "./static-initials.json" assert { type: "json" };
 import expressionInitial from "./expression-initial.json" assert { type: "json" };
 import expressionCalculated from "./expression-calculated.json" assert { type: "json" };
 import expressionEnableWhen from "./expression-enable-when.json" assert { type: "json" };
@@ -20,52 +21,57 @@ type DemoSample = {
 export const demoSamples: readonly DemoSample[] = [
   {
     id: "text-controls",
-    label: "1. Basic text inputs",
+    label: "Basic text inputs",
     questionnaire: textControls as Questionnaire,
   },
   {
     id: "boolean-gating",
-    label: "2. Boolean enableWhen",
+    label: "Boolean enableWhen",
     questionnaire: booleanGating as Questionnaire,
   },
   {
     id: "numeric-thresholds",
-    label: "3. Numeric comparisons",
+    label: "Numeric comparisons",
     questionnaire: numericThresholds as Questionnaire,
   },
   {
     id: "repeating-question",
-    label: "4. Repeating question answers",
+    label: "Repeating question answers",
     questionnaire: repeatingQuestion as Questionnaire,
   },
   {
     id: "repeating-group",
-    label: "5. Repeating group instances",
+    label: "Repeating group instances",
     questionnaire: repeatingGroup as Questionnaire,
   },
   {
     id: "nested-follow-ups",
-    label: "6. Nested follow-up questions",
+    label: "Nested follow-up questions",
     questionnaire: nestedFollowUps as Questionnaire,
   },
+  {
+    id: "static-initials",
+    label: "Static initial values",
+    questionnaire: staticInitials as Questionnaire,
+  },
   {
     id: "expression-initial",
-    label: "7. Initial expression defaults",
+    label: "Initial expression defaults",
     questionnaire: expressionInitial as Questionnaire,
   },
   {
     id: "expression-calculated",
-    label: "8. Calculated expressions",
+    label: "Calculated expressions",
     questionnaire: expressionCalculated as Questionnaire,
   },
   {
     id: "expression-enable-when",
-    label: "9. Expression-based enablement",
+    label: "Expression-based enablement",
     questionnaire: expressionEnableWhen as Questionnaire,
   },
   {
     id: "expression-dynamic-bounds",
-    label: "10. Dynamic min/max expressions",
+    label: "Dynamic min/max expressions",
     questionnaire: expressionDynamicBounds as Questionnaire,
   },
 ] as const;

demo/samples/static-initials.json

@@ -0,0 +1,95 @@
+{
+  "resourceType": "Questionnaire",
+  "id": "static-initials",
+  "status": "active",
+  "title": "Static Initial Values",
+  "description": "Shows how questionnaire.item.initial seeds single and repeating answers, including read-only fields and minOccurs padding.",
+  "item": [
+    {
+      "linkId": "intro",
+      "type": "display",
+      "text": "Static initial values come from the questionnaire item. Edit the nickname, add an extra care-team member, and notice the read-only review date stays locked."
+    },
+    {
+      "linkId": "profile",
+      "type": "group",
+      "text": "Patient profile",
+      "item": [
+        {
+          "linkId": "nickname",
+          "type": "string",
+          "text": "Preferred nickname",
+          "initial": [
+            {
+              "valueString": "Buddy"
+            }
+          ]
+        },
+        {
+          "linkId": "review-date",
+          "type": "date",
+          "text": "Last reviewed",
+          "readOnly": true,
+          "initial": [
+            {
+              "valueDate": "2025-10-30"
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "linkId": "care-team",
+      "type": "group",
+      "text": "Care team contacts",
+      "item": [
+        {
+          "linkId": "team-member",
+          "type": "string",
+          "text": "Team member name",
+          "repeats": true,
+          "extension": [
+            {
+              "url": "http://hl7.org/fhir/StructureDefinition/questionnaire-minOccurs",
+              "valueInteger": 3
+            },
+            {
+              "url": "http://hl7.org/fhir/StructureDefinition/questionnaire-maxOccurs",
+              "valueInteger": 4
+            }
+          ],
+          "initial": [
+            {
+              "valueString": "Primary Physician — Dr. Sloan"
+            },
+            {
+              "valueString": "Nurse Navigator — Casey Lee"
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "linkId": "vitals",
+      "type": "group",
+      "text": "Baseline vitals",
+      "item": [
+        {
+          "linkId": "baseline-weight",
+          "type": "quantity",
+          "text": "Weight",
+          "initial": [
+            {
+              "valueQuantity": {
+                "value": 72.5,
+                "unit": "kg",
+                "system": "http://unitsofmeasure.org",
+                "code": "kg"
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}

lib/stores/__tests__/calculated-expression.test.ts

@@ -204,6 +204,30 @@ describe("calculatedExpression", () => {
     ]);
   });
 
+  it("overwrites template initial values when calculated expressions run", () => {
+    const questionnaire: Questionnaire = {
+      resourceType: "Questionnaire",
+      status: "active",
+      item: [
+        {
+          linkId: "result",
+          type: "decimal",
+          initial: [{ valueDecimal: 5 }],
+          extension: [makeCalculatedExpression(undefined, "10")],
+        },
+      ],
+    };
+
+    const form = new FormStore(questionnaire);
+    const node = form.scope.lookupNode("result");
+
+    if (!node || !isQuestionNode(node)) {
+      throw new Error("Expected result question");
+    }
+
+    expect(node.answers[0]?.value).toBe(10);
+  });
+
   it("allows named calculated expressions to be reused", () => {
     const questionnaire: Questionnaire = {
       resourceType: "Questionnaire",