error[E0658]: box expression syntax is experimental; you can call `Box::new` instead. (see issue #27779) | |
--> $DIR/feature-gate-box_syntax.rs:14:13 | |
| | |
14 | let x = box 3; | |
| ^^^^^ | |
| | |
= help: add #![feature(box_syntax)] to the crate attributes to enable | |
error: aborting due to previous error | |