Function evaluatePropCore

packages/lang-core/src/runtime/evaluate-prop.ts:32–108

(
  value: unknown,
  context: EvaluationContext,
  schemaCtx: SchemaContext,
  reactiveSchema: unknown | undefined,
  callbacks: PropEvalCallbacks,
)

 * ReactiveAssign markers, nested ElementNodes, arrays, and ActionPlans.
 */
export function evaluatePropCore(
  value: unknown,
  context: EvaluationContext,
  schemaCtx: SchemaContext,
  reactiveSchema: unknown | undefined,
  callbacks: PropEvalCallbacks,
): unknown {
  if (value == null) return value;
  if (typeof value !== "object") return value;

  // AST node — evaluate with schema context
  if (isASTNode(value)) {
    // StateRef on reactive prop → ReactiveAssign marker
    if (value.k === "StateRef" && reactiveSchema && isReactiveSchema(reactiveSchema)) {
      return {
        __reactive: "assign" as const,
        target: value.n,
        expr: { k: "StateRef" as const, n: "$value" },
      };
    }
    const result = evaluate(value, context, schemaCtx);
    // ElementNode result (from ternary/Comp) → recurse into its props
    if (isElementNode(result)) {
      return callbacks.recurseElement(result as ElementNode);
    }
    // Array result (from Each) → recurse into any ElementNodes
    if (Array.isArray(result)) {
      return result.map((item) =>
        isElementNode(item) ? callbacks.recurseElement(item as ElementNode) : item,
      );
    }
    // Strip ReactiveAssign from non-reactive props
    if (isReactiveAssign(result) && !(reactiveSchema && isReactiveSchema(reactiveSchema))) {
      return context.getState(result.target) ?? null;
    }
    return result;
  }

  // String on reactive schema → pass through (component's useStateField resolves it)
  if (typeof value === "string" && reactiveSchema && isReactiveSchema(reactiveSchema)) {
    return value;
  }

  // Array — recurse
  if (Array.isArray(value)) {
    return value.map((v) => callbacks.recurse(v, reactiveSchema));
  }

  // ElementNode — recurse with schema
  if (isElementNode(value)) {
    return callbacks.recurseElement(value as ElementNode);
  }

  // ActionPlan / ActionStep — preserve as-is (deferred click-time evaluation)
  const obj = value as Record<string, unknown>;
  if ("steps" in obj && Array.isArray(obj.steps)) return value;
  if ("type" in obj && "valueAST" in obj) return value;