**Search Terms:** Type Array filter **Code** ```ts type T = { id:number }; const obj = [{id:1},{id:2},{id:3}] const ids = [1,2,5]; const error:T[] = ids.map(id=>obj[id] ? obj[id] : false).filter(Boolean); ``` **Expected behavior:** `const error` should be T[] only; **Actual behavior:** // error type is T | false **Related Issues:** <!-- Did you find other bugs that looked similar? --> [7657](https://github.com/microsoft/TypeScript/issues/7657)