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error[E0635]: unknown feature `const_default_impls`
--> $DIR/derive-const-use.rs:3:41
|
LL | #![feature(const_trait_impl, const_cmp, const_default_impls, derive_const, effects)]
| ^^^^^^^^^^^^^^^^^^^
error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
--> $DIR/derive-const-use.rs:7:12
|
LL | impl const Default for A {
| ^^^^^^^
|
= note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
= note: adding a non-const method body in the future would be a breaking change
error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
--> $DIR/derive-const-use.rs:7:6
|
LL | impl const Default for A {
| ^^^^^ unconstrained const parameter
|
= note: expressions using a const parameter must map each value to a distinct output value
= note: proving the result of expressions other than the parameter are unique is not supported
error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
--> $DIR/derive-const-use.rs:15:16
|
LL | #[derive_const(Default, PartialEq)]
| ^^^^^^^
|
= note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
= note: adding a non-const method body in the future would be a breaking change
= note: this error originates in the derive macro `Default` (in Nightly builds, run with -Z macro-backtrace for more info)
error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
|
= note: expressions using a const parameter must map each value to a distinct output value
= note: proving the result of expressions other than the parameter are unique is not supported
error[E0308]: mismatched types
--> $DIR/derive-const-use.rs:16:14
|
LL | #[derive_const(Default, PartialEq)]
| --------- in this derive macro expansion
LL | pub struct S((), A);
| ^^ expected `host`, found `true`
|
= note: expected constant `host`
found constant `true`
= note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
error: aborting due to 6 previous errors
Some errors have detailed explanations: E0207, E0308, E0635.
For more information about an error, try `rustc --explain E0207`.
|
