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`.