{"rules": {"@typescript-eslint/prefer-optional-chain": ["error"]  }}

declareconsta:{b:string|null}|null;a!==null&&a.b!==null&&a.b.length>0;/*^^^^^^^^^^^^^^^^^^^^^^^^^^ Prefer using an optional chain expression instead, as it's more concise and easier to read.*/

a?.b!=null&&a.b.length>0;

a?.b!==null&&a.b.length>0;/*                 ^ Object is possibly 'null'.*/