타입스크립트를 이용해 새로운 프로젝트를 진행하던 어느날 처음 보는 에러를 마주쳤습니다. element implicitly has an 'any' type because expression of type 'string' can't be used to index type '{ duelist: boolean; recon: boolean; sentinels: boolean; controllers: boolean; nodicision: boolean; }'. no index signature with a parameter of type 'string' was found on type '{ duelist: boolean; recon: boolean; sentinels: boolean; controllers: boo..