What does the following ‘using’ and ‘Symbol.dispose’ pattern guarantee? class DbConnection { [Symbol.dispose]() { this.close(); } close() { /* cleanup */ } } { using conn = new DbConnection(); // use conn }

Question

TypeScript Professional — Hard

What does the following ‘using’ and ‘Symbol.dispose’ pattern guarantee? class DbConnection { [Symbol.dispose]() { this.close(); } close() { /* cleanup */ } } { using conn = new DbConnection(); // use conn }

Accepted Answer

The 'using' and 'Symbol.dispose' pattern in the DbConnection class guarantees that conn.close() is automatically called when the block exits, ensuring deterministic resource cleanup without needing try-finally blocks.