function startAndEnd(start = 'start', end = 'end') {
  ...
}
function log<Input extends new (...args: any[]) => any>(
  value: Input,
  context: ClassDecoratorContext
) {
  if (context.kind === "class") {
    return class extends value {
      constructor(...args: any[]) {
        super(args);
      }
      log(msg: string): void {
        console.log(msg);
      }
    };
  }
  return value;
}
function bound(originalMethod: unknown, context: ClassMethodDecoratorContext<any>) {
  const methodName = context.name;
  if (context.kind === 'method') {
    context.addInitializer(function () {
      this[methodName] = this[methodName].bind(this);
    });
  }
}