Module rustc_middle::traits
source · Expand description
Trait Resolution. See the rustc dev guide for more information on how this works.
Re-exports
pub use self::select::EvaluationCache;
pub use self::select::EvaluationResult;
pub use self::select::OverflowError;
pub use self::select::SelectionCache;
pub use self::ObligationCauseCode::*;
Modules
- Experimental types for the trait query interface. The methods defined in this module are all based on canonicalization, which makes a canonical query by replacing unbound inference variables and regions, so that results can be reused more broadly. The providers for the queries defined here can be found in
rustc_traits
. - Candidate selection. See the rustc dev guide for more information on how this works.
Structs
- Identifies a particular impl in the source, along with a set of substitutions from the impl’s type/lifetime parameters. The
nested
vector corresponds to the nested obligations attached to the impl’s type parameters. - The reason why we incurred this obligation; used for error reporting.
Enums
- These are the error cases for
codegen_select_candidate
. - Given the successful resolution of an obligation, the
ImplSource
indicates where the impl comes from. - Reasons a method might not be object-safe.
- Depending on the stage of compilation, we want projection to be more or less conservative.
- The ‘location’ at which we try to perform HIR-based wf checking. This information is used to obtain an
hir::Ty
, which we can walk in order to obtain precise spans for any ‘nested’ types (e.g.Foo
inOption<Foo>
).
Type Aliases
- When performing resolution, it is typically the case that there can be one of three outcomes: