fix break

src/utils.ts

@@ -1,3 +1,18 @@
 export function encodeUtf8(s: string): Uint8Array {
   return new TextEncoder().encode(s);
 }
+
+export class Ids {
+  nextId: number = 0;
+
+  public next(): number {
+    return this.nextId++;
+  }
+}
+
+export function unwrap<T>(value: T | undefined): T {
+  if (value === undefined) {
+    throw new Error("tried to unwrap undefined value");
+  }
+  return value;
+}