webamp/packages/skin-database/data/UserContext.ts

// Currently only used as a WeakMap key
export default class UserContext {
  username: string | null;
  constructor(username?: string) {
    this.username = username || null;
  }
  authed() {
    return this.username != null;
  }
}

export function ctxWeakMapMemoize<T>(factory: () => T) {
  const cache: WeakMap<UserContext, T> = new WeakMap();
  return function get(ctx: UserContext): T {
    if (!cache.has(ctx)) {
      cache.set(ctx, factory());
    }
    // @ts-ignore We just put the value in there
    return cache.get(ctx);
  };
}