Struct rustc_trait_selection::traits::engine::ObligationCtxt

pub struct ObligationCtxt<'a, 'tcx, E = ScrubbedTraitError<'tcx>> {
    pub infcx: &'a InferCtxt<'tcx>,
    engine: RefCell<Box<dyn TraitEngine<'tcx, E>>>,
}

Used if you want to have pleasant experience when dealing with obligations outside of hir or mir typeck.

Fields

infcx: &'a InferCtxt<'tcx>

engine: RefCell<Box<dyn TraitEngine<'tcx, E>>>

Implementations

impl<'a, 'tcx> ObligationCtxt<'a, 'tcx, FulfillmentError<'tcx>>

pub fn new_with_diagnostics(infcx: &'a InferCtxt<'tcx>) -> Self

impl<'a, 'tcx> ObligationCtxt<'a, 'tcx, ScrubbedTraitError<'tcx>>

pub fn new(infcx: &'a InferCtxt<'tcx>) -> Self

impl<'a, 'tcx, E> ObligationCtxt<'a, 'tcx, E>

where E: 'tcx,

pub fn register_obligation(&self, obligation: PredicateObligation<'tcx>)

pub fn register_obligations( &self, obligations: impl IntoIterator<Item = PredicateObligation<'tcx>>, )

pub fn register_infer_ok_obligations<T>(&self, infer_ok: InferOk<'tcx, T>) -> T

pub fn register_bound( &self, cause: ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, ty: Ty<'tcx>, def_id: DefId, )

Requires that ty must implement the trait with def_id in the given environment. This trait must not have any type parameters (except for Self).

pub fn normalize<T: TypeFoldable<TyCtxt<'tcx>>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, value: T, ) -> T

pub fn eq<T: ToTrace<'tcx>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, expected: T, actual: T, ) -> Result<(), TypeError<'tcx>>

pub fn sub<T: ToTrace<'tcx>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, expected: T, actual: T, ) -> Result<(), TypeError<'tcx>>

Checks whether expected is a subtype of actual: expected <: actual.

pub fn relate<T: ToTrace<'tcx>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, variance: Variance, expected: T, actual: T, ) -> Result<(), TypeError<'tcx>>

pub fn sup<T: ToTrace<'tcx>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, expected: T, actual: T, ) -> Result<(), TypeError<'tcx>>

Checks whether expected is a supertype of actual: expected :> actual.

pub fn select_where_possible(&self) -> Vec<E>

pub fn select_all_or_error(&self) -> Vec<E>

pub fn into_pending_obligations(self) -> Vec<PredicateObligation<'tcx>>

Returns the not-yet-processed and stalled obligations from the ObligationCtxt.

Takes ownership of the context as doing operations such as ObligationCtxt::eq afterwards will result in other obligations getting ignored. You can make a new ObligationCtxt if this needs to be done in a loop, for example.

pub fn resolve_regions_and_report_errors( self, generic_param_scope: LocalDefId, outlives_env: &OutlivesEnvironment<'tcx>, ) -> Result<(), ErrorGuaranteed>

Resolves regions and reports errors.

Takes ownership of the context as doing trait solving afterwards will result in region constraints getting ignored.

pub fn resolve_regions( self, outlives_env: &OutlivesEnvironment<'tcx>, ) -> Vec<RegionResolutionError<'tcx>>

Resolves regions and reports errors.

Takes ownership of the context as doing trait solving afterwards will result in region constraints getting ignored.

impl<'tcx> ObligationCtxt<'_, 'tcx, FulfillmentError<'tcx>>

pub fn assumed_wf_types_and_report_errors( &self, param_env: ParamEnv<'tcx>, def_id: LocalDefId, ) -> Result<FxIndexSet<Ty<'tcx>>, ErrorGuaranteed>

impl<'tcx> ObligationCtxt<'_, 'tcx, ScrubbedTraitError<'tcx>>

pub fn make_canonicalized_query_response<T>( &self, inference_vars: CanonicalVarValues<'tcx>, answer: T, ) -> Result<CanonicalQueryResponse<'tcx, T>, NoSolution>

where T: Debug + TypeFoldable<TyCtxt<'tcx>>, Canonical<'tcx, QueryResponse<'tcx, T>>: ArenaAllocatable<'tcx>,

impl<'tcx, E> ObligationCtxt<'_, 'tcx, E>

where E: FromSolverError<'tcx, NextSolverError<'tcx>>,

pub fn assumed_wf_types( &self, param_env: ParamEnv<'tcx>, def_id: LocalDefId, ) -> Result<FxIndexSet<Ty<'tcx>>, Vec<E>>

pub fn deeply_normalize<T: TypeFoldable<TyCtxt<'tcx>>>( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, value: T, ) -> Result<T, Vec<E>>

pub fn structurally_normalize( &self, cause: &ObligationCause<'tcx>, param_env: ParamEnv<'tcx>, value: Ty<'tcx>, ) -> Result<Ty<'tcx>, Vec<E>>

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 32 bytes