1warning: trait method `try_into` will become ambiguous in Rust 2021 2 --> $DIR/future-prelude-collision-macros.rs:39:5 3 | 4LL | foo!().try_into(todo!()); 5 | ^^^^^^^^^^^^^^^^^^^^^^^^ help: disambiguate the associated function: `MyTry::try_into(foo!(), todo!())` 6 | 7 = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! 8 = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/prelude.html> 9note: the lint level is defined here 10 --> $DIR/future-prelude-collision-macros.rs:4:9 11 | 12LL | #![warn(rust_2021_prelude_collisions)] 13 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 14 15warning: trait-associated function `try_from` will become ambiguous in Rust 2021 16 --> $DIR/future-prelude-collision-macros.rs:42:5 17 | 18LL | <bar!()>::try_from(0); 19 | ^^^^^^^^^^^^^^^^^^ help: disambiguate the associated function: `<bar!() as TryFromU8>::try_from` 20 | 21 = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! 22 = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/prelude.html> 23 24warning: 2 warnings emitted 25 26