diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs index 956cb580d1032..a0a3a973fbeca 100644 --- a/compiler/rustc_ast_lowering/src/index.rs +++ b/compiler/rustc_ast_lowering/src/index.rs @@ -311,7 +311,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> { ); self.with_parent(const_arg.hir_id, |this| { - intravisit::walk_ambig_const_arg(this, const_arg); + intravisit::walk_const_arg(this, const_arg); }); } diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs index 556f50a85af7d..380120ecfe285 100644 --- a/compiler/rustc_hir/src/hir.rs +++ b/compiler/rustc_hir/src/hir.rs @@ -407,10 +407,8 @@ impl<'hir> PathSegment<'hir> { /// that are [just paths](ConstArgKind::Path) (currently just bare const params) /// versus const args that are literals or have arbitrary computations (e.g., `{ 1 + 3 }`). /// -/// The `Unambig` generic parameter represents whether the position this const is from is -/// unambiguously a const or ambiguous as to whether it is a type or a const. When in an -/// ambiguous context the parameter is instantiated with an uninhabited type making the -/// [`ConstArgKind::Infer`] variant unusable and [`GenericArg::Infer`] is used instead. +/// For an explanation of the `Unambig` generic parameter see the dev-guide: +/// #[derive(Clone, Copy, Debug, HashStable_Generic)] #[repr(C)] pub struct ConstArg<'hir, Unambig = ()> { @@ -422,7 +420,7 @@ pub struct ConstArg<'hir, Unambig = ()> { impl<'hir> ConstArg<'hir, AmbigArg> { /// Converts a `ConstArg` in an ambiguous position to one in an unambiguous position. /// - /// Functions accepting an unambiguous consts may expect the [`ConstArgKind::Infer`] variant + /// Functions accepting unambiguous consts may expect the [`ConstArgKind::Infer`] variant /// to be used. Care should be taken to separately handle infer consts when calling this /// function as it cannot be handled by downstream code making use of the returned const. /// @@ -3298,14 +3296,12 @@ impl<'hir> AssocItemConstraintKind<'hir> { #[derive(Debug, Clone, Copy, HashStable_Generic)] pub enum AmbigArg {} -#[derive(Debug, Clone, Copy, HashStable_Generic)] -#[repr(C)] /// Represents a type in the `HIR`. /// -/// The `Unambig` generic parameter represents whether the position this type is from is -/// unambiguously a type or ambiguous as to whether it is a type or a const. When in an -/// ambiguous context the parameter is instantiated with an uninhabited type making the -/// [`TyKind::Infer`] variant unusable and [`GenericArg::Infer`] is used instead. +/// For an explanation of the `Unambig` generic parameter see the dev-guide: +/// +#[derive(Debug, Clone, Copy, HashStable_Generic)] +#[repr(C)] pub struct Ty<'hir, Unambig = ()> { #[stable_hasher(ignore)] pub hir_id: HirId, @@ -3640,9 +3636,12 @@ pub enum InferDelegationKind { } /// The various kinds of types recognized by the compiler. -#[derive(Debug, Clone, Copy, HashStable_Generic)] +/// +/// For an explanation of the `Unambig` generic parameter see the dev-guide: +/// // SAFETY: `repr(u8)` is required so that `TyKind<()>` and `TyKind` are layout compatible #[repr(u8, C)] +#[derive(Debug, Clone, Copy, HashStable_Generic)] pub enum TyKind<'hir, Unambig = ()> { /// Actual type should be inherited from `DefId` signature InferDelegation(DefId, InferDelegationKind), diff --git a/compiler/rustc_hir/src/intravisit.rs b/compiler/rustc_hir/src/intravisit.rs index 57e49625148c2..aa96ff1eb1af8 100644 --- a/compiler/rustc_hir/src/intravisit.rs +++ b/compiler/rustc_hir/src/intravisit.rs @@ -364,9 +364,6 @@ pub trait Visitor<'v>: Sized { /// All types are treated as ambiguous types for the purposes of hir visiting in /// order to ensure that visitors can handle infer vars without it being too error-prone. /// - /// See the doc comments on [`Ty`] for an explanation of what it means for a type to be - /// ambiguous. - /// /// The [`Visitor::visit_infer`] method should be overridden in order to handle infer vars. fn visit_ty(&mut self, t: &'v Ty<'v, AmbigArg>) -> Self::Result { walk_ty(self, t) @@ -375,12 +372,9 @@ pub trait Visitor<'v>: Sized { /// All consts are treated as ambiguous consts for the purposes of hir visiting in /// order to ensure that visitors can handle infer vars without it being too error-prone. /// - /// See the doc comments on [`ConstArg`] for an explanation of what it means for a const to be - /// ambiguous. - /// /// The [`Visitor::visit_infer`] method should be overridden in order to handle infer vars. fn visit_const_arg(&mut self, c: &'v ConstArg<'v, AmbigArg>) -> Self::Result { - walk_ambig_const_arg(self, c) + walk_const_arg(self, c) } #[allow(unused_variables)] @@ -525,7 +519,7 @@ pub trait VisitorExt<'v>: Visitor<'v> { /// Named `visit_const_arg_unambig` instead of `visit_unambig_const_arg` to aid in /// discovery by IDes when `v.visit_const_arg` is written. fn visit_const_arg_unambig(&mut self, c: &'v ConstArg<'v>) -> Self::Result { - walk_const_arg(self, c) + walk_unambig_const_arg(self, c) } } impl<'v, V: Visitor<'v>> VisitorExt<'v> for V {} @@ -980,7 +974,6 @@ pub fn walk_unambig_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v>) -> Some(ambig_ty) => visitor.visit_ty(ambig_ty), None => { let Ty { hir_id, span, kind: _ } = typ; - try_visit!(visitor.visit_id(*hir_id)); visitor.visit_infer(*hir_id, *span, InferKind::Ty(typ)) } } @@ -1038,7 +1031,7 @@ pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v, AmbigArg>) - V::Result::output() } -pub fn walk_const_arg<'v, V: Visitor<'v>>( +pub fn walk_unambig_const_arg<'v, V: Visitor<'v>>( visitor: &mut V, const_arg: &'v ConstArg<'v>, ) -> V::Result { @@ -1046,13 +1039,12 @@ pub fn walk_const_arg<'v, V: Visitor<'v>>( Some(ambig_ct) => visitor.visit_const_arg(ambig_ct), None => { let ConstArg { hir_id, kind: _ } = const_arg; - try_visit!(visitor.visit_id(*hir_id)); visitor.visit_infer(*hir_id, const_arg.span(), InferKind::Const(const_arg)) } } } -pub fn walk_ambig_const_arg<'v, V: Visitor<'v>>( +pub fn walk_const_arg<'v, V: Visitor<'v>>( visitor: &mut V, const_arg: &'v ConstArg<'v, AmbigArg>, ) -> V::Result {