error[E0635]: unknown feature `tuple_trait` | |
--> $DIR/lang-item-missing-generator.rs:2:51 | |
| | |
LL | #![feature(no_core, lang_items, unboxed_closures, tuple_trait)] | |
| ^^^^^^^^^^^ | |
error: requires `generator` lang_item | |
--> $DIR/lang-item-missing-generator.rs:17:17 | |
| | |
LL | pub fn abc() -> impl FnOnce(f32) { | |
| ^^^^^^^^^^^^^^^^ | |
error: aborting due to 2 previous errors | |
For more information about this error, try `rustc --explain E0635`. |