Module hir_ty_lowering 

HIR ty lowering: Lowers type-system entities¹ from the HIR to the rustc_middle::ty representation.

Not to be confused with AST lowering which lowers AST constructs to HIR ones or with THIR / MIR lowering / building which lowers HIR bodies (i.e., “executable code”) to THIR / MIR.

Most lowering routines are defined on dyn HirTyLowerer directly, like the main routine of this module, lower_ty.

This module used to be called astconv.

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1. This includes types, lifetimes / regions, constants in type positions, trait references and bounds. ↩

Re-exports

use std::assert_matches; 🔒

use std::slice; 🔒

use rustc_abi::FIRST_VARIANT; 🔒

use rustc_ast::LitKind; 🔒

use rustc_attr_ir::lang_items::LangItem; 🔒

use rustc_data_structures::fx::FxHashSet; 🔒

use rustc_data_structures::fx::FxIndexMap; 🔒

use rustc_data_structures::fx::FxIndexSet; 🔒

use rustc_data_structures::sso::SsoHashSet; 🔒

use rustc_data_structures::thin_vec::ThinVec; 🔒

use rustc_errors::Applicability; 🔒

use rustc_errors::Diag; 🔒

use rustc_errors::DiagCtxtHandle; 🔒

use rustc_errors::ErrorGuaranteed; 🔒

use rustc_errors::FatalError; 🔒

use rustc_errors::StashKey; 🔒

use rustc_errors::struct_span_code_err; 🔒

use rustc_hir::def::CtorKind; 🔒

use rustc_hir::def::CtorOf; 🔒

use rustc_hir::def::DefKind; 🔒

use rustc_hir::def::Res; 🔒

use rustc_hir::def_id::DefId; 🔒

use rustc_hir::def_id::LocalDefId; 🔒

use rustc_hir as hir; 🔒

use rustc_hir::AnonConst; 🔒

use rustc_hir::GenericArg; 🔒

use rustc_hir::GenericArgs; 🔒

use rustc_hir::HirId; 🔒

use rustc_infer::infer::InferCtxt; 🔒

use rustc_infer::infer::TyCtxtInferExt; 🔒

use rustc_infer::traits::DynCompatibilityViolation; 🔒

use rustc_lint_defs::builtin::AMBIGUOUS_ASSOCIATED_ITEMS; 🔒

use rustc_macros::TypeFoldable; 🔒

use rustc_macros::TypeVisitable; 🔒

use rustc_middle::middle::stability::AllowUnstable; 🔒

use rustc_middle::ty; 🔒

use rustc_middle::ty::Const; 🔒

use rustc_middle::ty::FnSigKind; 🔒

use rustc_middle::ty::GenericArgKind; 🔒

use rustc_middle::ty::GenericArgsRef; 🔒

use rustc_middle::ty::GenericParamDefKind; 🔒

use rustc_middle::ty::LitToConstInput; 🔒

use rustc_middle::ty::Ty; 🔒

use rustc_middle::ty::TyCtxt; 🔒

use rustc_middle::ty::TypeSuperFoldable; 🔒

use rustc_middle::ty::TypeVisitableExt; 🔒

use rustc_middle::ty::TypingMode; 🔒

use rustc_middle::ty::Unnormalized; 🔒

use rustc_middle::ty::Upcast; 🔒

use rustc_middle::ty::const_lit_matches_ty; 🔒

use rustc_middle::ty::fold_regions; 🔒

use rustc_session::diagnostics::feature_err; 🔒

use rustc_span::def_id::LocalModId; 🔒

use rustc_span::def_id::ModId; 🔒

use rustc_span::DUMMY_SP; 🔒

use rustc_span::Ident; 🔒

use rustc_span::Span; 🔒

use rustc_span::bug; 🔒

use rustc_span::kw; 🔒

use rustc_span::span_bug; 🔒

use rustc_span::sym; 🔒

use rustc_trait_selection::infer::InferCtxtExt; 🔒

use rustc_trait_selection::traits; 🔒

use rustc_trait_selection::traits::FulfillmentError; 🔒

use tracing::debug; 🔒

use tracing::instrument; 🔒

use tracing::instrument; 🔒

use crate::check::check_abi; 🔒

use crate::check_c_variadic_abi; 🔒

use crate::diagnostics; 🔒

use crate::diagnostics::BadReturnTypeNotation; 🔒

use crate::diagnostics::NoFieldOnType; 🔒

use crate::diagnostics::NoVariantNamed; 🔒

use crate::hir_ty_lowering::errors::GenericsArgsErrExtend; 🔒

use crate::hir_ty_lowering::errors::eq_ctxt_suggestion_span; 🔒

use crate::hir_ty_lowering::errors::prohibit_assoc_item_constraint; 🔒

use crate::hir_ty_lowering::generics::check_generic_arg_count; 🔒

use crate::hir_ty_lowering::generics::lower_generic_args; 🔒

use crate::middle::resolve_bound_vars as rbv; 🔒

use rustc_errors::codes::*; 🔒

Modules

bounds 🔒

cmse 🔒

dyn_trait 🔒

errors

generics

Structs

ForbidParamUsesFolder 🔒

GenericArgCountMismatch

A marker denoting that the generic arguments that were provided did not match the respective generic parameters.

GenericArgCountResult

Decorates the result of a generic argument count mismatch check with whether explicit late bounds were provided.

GenericPathSegment

A path segment that is semantically allowed to have generic arguments.

InherentAssocCandidate

ResolvedStructPath

Enums

AssocItemQSelf 🔒

The “qualified self” of an associated item path.

ExplicitLateBound

New-typed boolean indicating whether explicit late-bound lifetimes are present in a set of generic arguments.

ForbidParamContext 🔒

Context in which ForbidParamUsesFolder is being used, to emit appropriate diagnostics.

GenericArgPosition 🔒

Denotes the “position” of a generic argument, indicating if it is a generic type, generic function or generic method call.

ImpliedBoundsContext 🔒

The context in which an implied bound is being added to a item being lowered (i.e. a sizedness trait or a default trait)

IsMethodCall

LowerTypeRelativePathMode 🔒

OverlappingAsssocItemConstraints 🔒

Whether to allow duplicate associated iten constraints in a trait ref, e.g. Trait<Assoc = Ty, Assoc = Ty>. This is forbidden in dyn Trait<...> but allowed everywhere else.

PermitVariants

Whether to permit a path to resolve to an enum variant.

PredicateFilter

RegionInferReason

TypeRelativePath 🔒

Traits

GenericArgsLowerer

A context which can lower HIR’s GenericArg to rustc_middle’s ty::GenericArg.

HirTyLowerer

A context which can lower type-system entities from the HIR to the rustc_middle::ty representation.