fix: compile typed catches and reject event loop syntax

packages/syntax/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@wrnexus/syntax",
-  "version": "0.8.8",
+  "version": "0.8.9",
   "type": "module",
   "main": "src/index.ts",
   "exports": {

packages/syntax/src/diagnostics.ts

@@ -246,6 +246,18 @@ function astDiagnostics(ast: PageAst, options: DiagnoseOptions): WrnDiagnostic[]
     const tag = node.tag.toLowerCase();
 
     for (const attribute of node.attrs) {
+      if (attribute.event && (attribute.name === "for" || attribute.name === "key")) {
+        diagnostics.push({
+          code: "WRN-TEMPLATE-LOOP-DIRECTIVE",
+          severity: "error",
+          message: `@${attribute.name} is an event binding, not a loop directive.`,
+          hint:
+            attribute.name === "for"
+              ? 'Use data-for="item in items".'
+              : 'Use data-key="item.id" alongside data-for.',
+          file: options.file,
+        });
+      }
       if (attribute.event || attribute.boolean || !urlAttributes.has(attribute.name.toLowerCase()))
         continue;
       if (attribute.value.includes("{")) continue;

packages/syntax/src/types.ts

@@ -63,16 +63,18 @@ export function validateTypedInitializer(
  * Server output retains the original typed source.
  */
 export function eraseFunctionTypes(source: string): string {
-  return source.replace(
-    /(\b(?:async\s+)?function\s+[A-Za-z_$][\w$]*\s*\()([^)]*)(\)\s*)(?::\s*([^{}=>]+)\s*)?(\{)/g,
-    (_whole, open: string, params: string, close: string, _returnType: string, brace: string) => {
-      const plainParams = params
-        .split(",")
-        .map((param) =>
-          param.replace(/([A-Za-z_$][\w$]*)(\?)?\s*:\s*([^=]+?)(?=\s*=|$)/, "$1").trim(),
-        )
-        .join(", ");
-      return `${open}${plainParams}${close}${brace}`;
-    },
-  );
+  return source
+    .replace(/\bcatch\s*\(\s*([A-Za-z_$][\w$]*)\s*:\s*(?:any|unknown)\s*\)/g, "catch ($1)")
+    .replace(
+      /(\b(?:async\s+)?function\s+[A-Za-z_$][\w$]*\s*\()([^)]*)(\)\s*)(?::\s*([^{}=>]+)\s*)?(\{)/g,
+      (_whole, open: string, params: string, close: string, _returnType: string, brace: string) => {
+        const plainParams = params
+          .split(",")
+          .map((param) =>
+            param.replace(/([A-Za-z_$][\w$]*)(\?)?\s*:\s*([^=]+?)(?=\s*=|$)/, "$1").trim(),
+          )
+          .join(", ");
+        return `${open}${plainParams}${close}${brace}`;
+      },
+    );
 }

packages/syntax/test/v060.test.ts

@@ -1,5 +1,5 @@
 import { expect, test } from "bun:test";
-import { diagnose, parse } from "../src/index.ts";
+import { diagnose, eraseFunctionTypes, parse } from "../src/index.ts";
 
 const source = `import type { PublicUser } from "@/types/user.ts"
 import PublicLayout from "@/layouts/PublicLayout.wrn"
@@ -118,3 +118,20 @@ test("readonly prop diagnostics still reject direct prop assignments", () => {
   }`);
   expect(diagnostics.some((diagnostic) => diagnostic.code === "WRN-PROP-READONLY")).toBe(true);
 });
+
+test("browser type erasure removes typed catch bindings", () => {
+  const source = `async function load(): Promise<void> {
+    try { await fetch("/api") } catch (error: any) { console.error(error) }
+  }`;
+  expect(eraseFunctionTypes(source)).toContain("catch (error)");
+  expect(eraseFunctionTypes(source)).not.toContain(": any");
+});
+
+test("diagnoses event syntax mistakenly used for loop directives", () => {
+  const diagnostics = diagnose(`component Rows {
+    view { <ul><li @for="row in rows" @key="row.id">{row.name}</li></ul> }
+  }`);
+  expect(diagnostics.filter((entry) => entry.code === "WRN-TEMPLATE-LOOP-DIRECTIVE")).toHaveLength(
+    2,
+  );
+});