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Contract variables can be declared in the `requires` clause and can be referenced both in `requires` and `ensures`, subject to usual borrow checking rules. This allows any setup common to both the `requires` and `ensures` clauses to only be done once.
20 lines
528 B
Rust
20 lines
528 B
Rust
//@ run-pass
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//@ compile-flags: -Zcontract-checks=yes
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#![feature(contracts)]
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//~^ WARN the feature `contracts` is incomplete and may not be safe to use and/or cause compiler crashes [incomplete_features]
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extern crate core;
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use core::contracts::{ensures, requires};
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// checks that variable declarations are lowered properly, with the ability to
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// refer to them *both* in requires and ensures
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#[requires(let y = 2 * x; y > 0)]
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#[ensures(move |ret| { *ret == y })]
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fn foo(x: u32) -> u32 {
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x * 2
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}
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fn main() {
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foo(1);
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}
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