error[E0277]: a `try` block must return `Result` or `Option` (or another type that implements `Try`) --> $DIR/try-block-in-while.rs:6:17 | LL | while try { false } {} | ^^^^^ could not wrap the final value of the block as `bool` doesn't implement `Try` | = help: the trait `Try` is not implemented for `bool` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.