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import { Actor } from './Actor';
const children = new Map<string, Actor>();
let sessionIdIndex = 0;
export interface Registry {  bookId(): string;  register(id: string, actor: Actor): string;  get(id: string): Actor | undefined;  free(id: string): void;}
export const registry: Registry = {  bookId() {    return `x:${sessionIdIndex++}`;  },  register(id, actor) {    children.set(id, actor);    return id;  },  get(id) {    return children.get(id);  },  free(id) {    children.delete(id);  }};