c5598d6a9e
avoid `{type error}` being leaked in user-facing messages,
particularly when using the `adt_const_params` feature
43 lines
1.8 KiB
Plaintext
43 lines
1.8 KiB
Plaintext
error: generic parameters may not be used in const operations
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--> $DIR/issue-68366.rs:12:37
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LL | impl <const N: usize> Collatz<{Some(N)}> {}
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| ^ cannot perform const operation using `N`
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= help: const parameters may only be used as standalone arguments, i.e. `N`
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= help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
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error: `Option<usize>` is forbidden as the type of a const generic parameter
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--> $DIR/issue-68366.rs:9:25
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LL | struct Collatz<const N: Option<usize>>;
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| ^^^^^^^^^^^^^
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= note: the only supported types are integers, `bool`, and `char`
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help: add `#![feature(adt_const_params)]` to the crate attributes to enable more complex and user defined types
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LL + #![feature(adt_const_params)]
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error[E0207]: the const parameter `N` is not constrained by the impl trait, self type, or predicates
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--> $DIR/issue-68366.rs:12:7
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LL | impl <const N: usize> Collatz<{Some(N)}> {}
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| ^^^^^^^^^^^^^^ unconstrained const parameter
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= note: expressions using a const parameter must map each value to a distinct output value
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= note: proving the result of expressions other than the parameter are unique is not supported
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error[E0207]: the const parameter `N` is not constrained by the impl trait, self type, or predicates
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--> $DIR/issue-68366.rs:19:6
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LL | impl<const N: usize> Foo {}
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| ^^^^^^^^^^^^^^ unconstrained const parameter
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= note: expressions using a const parameter must map each value to a distinct output value
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= note: proving the result of expressions other than the parameter are unique is not supported
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error: aborting due to 4 previous errors
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For more information about this error, try `rustc --explain E0207`.
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