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Address the change in https://github.com/rust-lang/rust/pull/106718 

Signed-off-by: Yuki Okushi <jtitor@2k36.org>
This commit is contained in:
Yuki Okushi 2023-02-03 00:00:10 +09:00 committed by Tshepang Mbambo
parent 6213fc1cf5
commit 6ea7b0db51
1 changed files with 4 additions and 4 deletions
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6
src/solve/trait-solving.md
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@ -29,7 +29,7 @@ have to prove and the `param_env` in which this predicate has to hold.
We prove goals by checking whether each possible [`Candidate`] applies for the given goal by We prove goals by checking whether each possible [`Candidate`] applies for the given goal by
recursively proving its nested goals. For a list of possible candidates with examples, look at recursively proving its nested goals. For a list of possible candidates with examples, look at
[`CandidateSource`]. The most important candidates are `Impl` candidates, i.e. trait implementations [`CandidateSource`]. The most important candidates are `Impl` candidates, i.e. trait implementations
written by the user, and `ParamEnv` candidates, i.e. assumptions in our current environment. written by the user, and `ParamEnv` candidates, i.e. assumptions in our current environment.
Looking at the above example, to prove `Vec<T>: Clone` we first use Looking at the above example, to prove `Vec<T>: Clone` we first use
`impl<T: Clone> Clone for Vec<T>`. To use this impl we have to prove the nested `impl<T: Clone> Clone for Vec<T>`. To use this impl we have to prove the nested
@ -64,7 +64,7 @@ We can however get overflow as in the following snippet:
fn foo<T: Trait>(x: ) fn foo<T: Trait>(x: )
``` ```
### 3. Trait goals in empty environments are proven by a unique impl. ### 3. Trait goals in empty environments are proven by a unique impl
If a trait goal holds with an empty environment, there is a unique `impl`, If a trait goal holds with an empty environment, there is a unique `impl`,
either user-defined or builtin, which is used to prove that goal. either user-defined or builtin, which is used to prove that goal.
@ -110,5 +110,5 @@ Two types being equal in the type system must mean that they have the same `Type
[`Goal`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/struct.Goal.html [`Goal`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/struct.Goal.html
[`Predicate`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.Predicate.html [`Predicate`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.Predicate.html
[`Candidate`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/assembly/struct.Candidate.html [`Candidate`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/assembly/struct.Candidate.html
[`CandidateSource`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/trait_goals/enum.CandidateSource.html [`CandidateSource`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/assembly/enum.CandidateSource.html
[`CanonicalResponse`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/type.CanonicalResponse.html [`CanonicalResponse`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_trait_selection/solve/type.CanonicalResponse.html