| //! Unstable module containing the unstable contracts lang items and attribute macros. |
| |
| pub use crate::macros::builtin::{contracts_ensures as ensures, contracts_requires as requires}; |
| |
| /// This is an identity function used as part of the desugaring of the `#[ensures]` attribute. |
| /// |
| /// This is an existing hack to allow users to omit the type of the return value in their ensures |
| /// attribute. |
| /// |
| /// Ideally, rustc should be able to generate the type annotation. |
| /// The existing lowering logic makes it rather hard to add the explicit type annotation, |
| /// while the function call is fairly straight forward. |
| #[unstable(feature = "contracts_internals", issue = "128044" /* compiler-team#759 */)] |
| // Similar to `contract_check_requires`, we need to use the user-facing |
| // `contracts` feature rather than the perma-unstable `contracts_internals`. |
| // Const-checking doesn't honor allow_internal_unstable logic used by contract expansion. |
| #[rustc_const_unstable(feature = "contracts", issue = "128044")] |
| #[lang = "contract_build_check_ensures"] |
| pub const fn build_check_ensures<Ret, C>(cond: C) -> C |
| where |
| C: Fn(&Ret) -> bool + Copy + 'static, |
| { |
| cond |
| } |
