Addressed points raised in review.
This commit is contained in:
parent
5bf5994d92
commit
f472cd9c02
@ -626,9 +626,6 @@ pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty) {
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TyKind::CVarArgs(ref lt) => {
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visitor.visit_lifetime(lt)
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}
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TyKind::AssocTyExistential(ref bounds) => {
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walk_list!(visitor, visit_param_bound, bounds);
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}
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TyKind::Infer | TyKind::Err => {}
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}
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}
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@ -677,7 +674,14 @@ pub fn walk_assoc_type_binding<'v, V: Visitor<'v>>(visitor: &mut V,
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type_binding: &'v TypeBinding) {
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visitor.visit_id(type_binding.hir_id);
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visitor.visit_ident(type_binding.ident);
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visitor.visit_ty(&type_binding.ty);
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match type_binding.kind {
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TypeBindingKind::Equality { ref ty } => {
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visitor.visit_ty(ty);
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}
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TypeBindingKind::Constraint { ref bounds } => {
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walk_list!(visitor, visit_param_bound, bounds);
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}
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}
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}
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pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat) {
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@ -1377,9 +1377,10 @@ impl<'a> LoweringContext<'a> {
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-> hir::TypeBinding {
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debug!("lower_assoc_ty_constraint(constraint={:?}, itctx={:?})", c, itctx);
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// Convert to a type representing the `T::Item` value.
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let ty = match c.kind {
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AssocTyConstraintKind::Equality { ref ty } => self.lower_ty(ty, itctx),
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let kind = match c.kind {
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AssocTyConstraintKind::Equality { ref ty } => hir::TypeBindingKind::Equality {
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ty: self.lower_ty(ty, itctx)
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},
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AssocTyConstraintKind::Bound { ref bounds } => {
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// Piggy-back on the `impl Trait` context to figure out the correct behavior.
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let (desugar_to_impl_trait, itctx) = match itctx {
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@ -1422,7 +1423,7 @@ impl<'a> LoweringContext<'a> {
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if desugar_to_impl_trait {
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// Desugar `AssocTy: Bounds` into `AssocTy = impl Bounds`. We do this by
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// constructing the HIR for "impl bounds" and then lowering that.
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// constructing the HIR for `impl bounds...` and then lowering that.
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let impl_trait_node_id = self.sess.next_node_id();
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let parent_def_index = self.current_hir_id_owner.last().unwrap().0;
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@ -1436,27 +1437,27 @@ impl<'a> LoweringContext<'a> {
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);
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self.with_dyn_type_scope(false, |this| {
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this.lower_ty(
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let ty = this.lower_ty(
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&Ty {
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id: this.sess.next_node_id(),
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node: TyKind::ImplTrait(impl_trait_node_id, bounds.clone()),
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span: DUMMY_SP,
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},
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itctx,
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)
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);
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hir::TypeBindingKind::Equality {
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ty
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}
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})
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} else {
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// Desugar `AssocTy: Bounds` into `AssocTy = ∃ T (T: Bounds)`, where the
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// "false existential" later desugars into a trait predicate.
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// Desugar `AssocTy: Bounds` into a type binding where the
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// later desugars into a trait predicate.
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let bounds = self.lower_param_bounds(bounds, itctx);
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let id = self.sess.next_node_id();
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P(hir::Ty {
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hir_id: self.lower_node_id(id),
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node: hir::TyKind::AssocTyExistential(bounds),
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span: DUMMY_SP,
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})
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hir::TypeBindingKind::Constraint {
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bounds
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}
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}
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}
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};
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@ -1464,7 +1465,7 @@ impl<'a> LoweringContext<'a> {
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hir::TypeBinding {
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hir_id: self.lower_node_id(c.id),
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ident: c.ident,
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ty,
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kind,
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span: c.span,
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}
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}
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@ -2359,10 +2360,17 @@ impl<'a> LoweringContext<'a> {
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hir::TypeBinding {
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hir_id: this.next_id(),
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ident: Ident::with_empty_ctxt(FN_OUTPUT_NAME),
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ty: output
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.as_ref()
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.map(|ty| this.lower_ty(&ty, ImplTraitContext::disallowed()))
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.unwrap_or_else(|| P(mk_tup(this, hir::HirVec::new(), span))),
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kind: hir::TypeBindingKind::Equality {
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ty: output
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.as_ref()
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.map(|ty| this.lower_ty(
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&ty,
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ImplTraitContext::disallowed()
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))
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.unwrap_or_else(||
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P(mk_tup(this, hir::HirVec::new(), span))
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),
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},
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span: output.as_ref().map_or(span, |ty| ty.span),
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}
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],
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@ -2666,7 +2674,9 @@ impl<'a> LoweringContext<'a> {
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args: hir_vec![],
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bindings: hir_vec![hir::TypeBinding {
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ident: Ident::with_empty_ctxt(FN_OUTPUT_NAME),
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ty: output_ty,
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kind: hir::TypeBindingKind::Equality {
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ty: output_ty,
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},
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hir_id: self.next_id(),
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span,
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}],
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@ -1780,7 +1780,7 @@ pub struct ImplItem {
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pub span: Span,
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}
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/// Represents different contents within `impl`s.
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/// Represents various kinds of content within an `impl`.
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#[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
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pub enum ImplItemKind {
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/// An associated constant of the given type, set to the constant result
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@ -1794,16 +1794,51 @@ pub enum ImplItemKind {
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Existential(GenericBounds),
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}
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// Bind a type to an associated type (`A = Foo`).
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/// Bind a type to an associated type (i.e., `A = Foo`).
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///
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/// Bindings like `A: Debug` are represented as a special type `A =
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/// $::Debug` that is understood by the astconv code.
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///
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/// FIXME(alexreg) -- why have a separate type for the binding case,
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/// wouldn't it be better to make the `ty` field an enum like:
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///
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/// ```
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/// enum TypeBindingKind {
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/// Equals(...),
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/// Binding(...),
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/// }
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/// ```
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#[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
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pub struct TypeBinding {
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pub hir_id: HirId,
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#[stable_hasher(project(name))]
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pub ident: Ident,
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pub ty: P<Ty>,
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pub kind: TypeBindingKind,
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pub span: Span,
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}
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// Represents the two kinds of type bindings.
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#[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
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pub enum TypeBindingKind {
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/// E.g., `Foo<Bar: Send>`.
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Constraint {
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bounds: HirVec<GenericBound>,
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},
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/// E.g., `Foo<Bar = ()>`.
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Equality {
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ty: P<Ty>,
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},
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}
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impl TypeBinding {
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pub fn ty(&self) -> &Ty {
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match self.kind {
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TypeBindingKind::Equality { ref ty } => ty,
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_ => bug!("expected equality type binding for parenthesized generic args"),
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}
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}
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}
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#[derive(Clone, RustcEncodable, RustcDecodable)]
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pub struct Ty {
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pub hir_id: HirId,
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@ -1898,8 +1933,6 @@ pub enum TyKind {
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/// Placeholder for C-variadic arguments. We "spoof" the `VaList` created
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/// from the variadic arguments. This type is only valid up to typeck.
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CVarArgs(Lifetime),
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/// The existential type (i.e., `impl Trait`) that constrains an associated type.
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AssocTyExistential(HirVec<GenericBound>),
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}
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#[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
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@ -2236,18 +2269,18 @@ impl StructField {
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}
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}
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/// Fields and constructor ids of enum variants and structs
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/// Fields and constructor IDs of enum variants and structs.
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#[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
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pub enum VariantData {
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/// Struct variant.
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/// A struct variant.
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///
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/// e.g., `Bar { .. }` as in `enum Foo { Bar { .. } }`.
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/// E.g., `Bar { .. }` as in `enum Foo { Bar { .. } }`.
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Struct(HirVec<StructField>, /* recovered */ bool),
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/// Tuple variant.
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/// A tuple variant.
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///
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/// E.g., `Bar(..)` as in `enum Foo { Bar(..) }`.
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Tuple(HirVec<StructField>, HirId),
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/// Unit variant.
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/// A unit variant.
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///
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/// E.g., `Bar = ..` as in `enum Foo { Bar = .. }`.
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Unit(HirId),
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@ -409,9 +409,6 @@ impl<'a> State<'a> {
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hir::TyKind::CVarArgs(_) => {
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self.s.word("...")?;
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}
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hir::TyKind::AssocTyExistential(ref bounds) => {
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self.print_bounds(":", bounds)?;
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}
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}
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self.end()
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}
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@ -1648,7 +1645,7 @@ impl<'a> State<'a> {
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self.space_if_not_bol()?;
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self.word_space("->")?;
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self.print_type(&generic_args.bindings[0].ty)?;
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self.print_type(generic_args.bindings[0].ty())?;
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} else {
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let start = if colons_before_params { "::<" } else { "<" };
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let empty = Cell::new(true);
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@ -1693,8 +1690,15 @@ impl<'a> State<'a> {
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start_or_comma(self)?;
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self.print_ident(binding.ident)?;
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self.s.space()?;
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self.word_space("=")?;
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self.print_type(&binding.ty)?;
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match generic_args.bindings[0].kind {
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hir::TypeBindingKind::Equality { ref ty } => {
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self.word_space("=")?;
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self.print_type(ty)?;
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}
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hir::TypeBindingKind::Constraint { ref bounds } => {
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self.print_bounds(":", bounds)?;
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}
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}
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}
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if !empty.get() {
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@ -923,7 +923,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
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fn visit_fn_decl(&mut self, fd: &'tcx hir::FnDecl) {
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let output = match fd.output {
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hir::DefaultReturn(_) => None,
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hir::Return(ref ty) => Some(ty),
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hir::Return(ref ty) => Some(&**ty),
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};
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self.visit_fn_like_elision(&fd.inputs, output);
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}
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@ -1884,7 +1884,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
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if generic_args.parenthesized {
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let was_in_fn_syntax = self.is_in_fn_syntax;
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self.is_in_fn_syntax = true;
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self.visit_fn_like_elision(generic_args.inputs(), Some(&generic_args.bindings[0].ty));
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self.visit_fn_like_elision(generic_args.inputs(), Some(generic_args.bindings[0].ty()));
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self.is_in_fn_syntax = was_in_fn_syntax;
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return;
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}
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@ -2020,7 +2020,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
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}
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}
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fn visit_fn_like_elision(&mut self, inputs: &'tcx [hir::Ty], output: Option<&'tcx P<hir::Ty>>) {
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fn visit_fn_like_elision(&mut self, inputs: &'tcx [hir::Ty], output: Option<&'tcx hir::Ty>) {
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debug!("visit_fn_like_elision: enter");
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let mut arg_elide = Elide::FreshLateAnon(Cell::new(0));
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let arg_scope = Scope::Elision {
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@ -710,10 +710,11 @@ impl<'o, 'gcx: 'tcx, 'tcx> dyn AstConv<'gcx, 'tcx> + 'o {
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// back separately.
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let assoc_bindings = generic_args.bindings.iter()
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.map(|binding| {
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let kind = if let hir::TyKind::AssocTyExistential(ref bounds) = binding.ty.node {
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ConvertedBindingKind::Constraint(bounds.clone())
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} else {
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ConvertedBindingKind::Equality(self.ast_ty_to_ty(&binding.ty))
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let kind = match binding.kind {
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hir::TypeBindingKind::Equality { ref ty } =>
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ConvertedBindingKind::Equality(self.ast_ty_to_ty(ty)),
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hir::TypeBindingKind::Constraint { ref bounds } =>
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ConvertedBindingKind::Constraint(bounds.clone()),
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};
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ConvertedBinding {
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item_name: binding.ident,
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@ -2060,10 +2061,6 @@ impl<'o, 'gcx: 'tcx, 'tcx> dyn AstConv<'gcx, 'tcx> + 'o {
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let region = self.ast_region_to_region(<, None);
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tcx.type_of(va_list_did).subst(tcx, &[region.into()])
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}
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hir::TyKind::AssocTyExistential(..) => {
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// Type is never actually used.
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tcx.types.err
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}
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hir::TyKind::Err => {
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tcx.types.err
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}
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@ -626,7 +626,9 @@ impl<'a, 'tcx> AutoTraitFinder<'a, 'tcx> {
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} => {
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bindings.push(TypeBinding {
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name: left_name.clone(),
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ty: rhs,
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kind: TypeBindingKind::Equality {
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ty: rhs,
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},
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});
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}
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&mut GenericArgs::Parenthesized { .. } => {
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|
@ -1979,7 +1979,7 @@ impl FnDecl {
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match &bounds[0] {
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GenericBound::TraitBound(PolyTrait { trait_, .. }, ..) => {
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let bindings = trait_.bindings().unwrap();
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FunctionRetTy::Return(bindings[0].ty.clone())
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FunctionRetTy::Return(bindings[0].ty().clone())
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}
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_ => panic!("unexpected desugaring of async function"),
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}
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@ -2937,11 +2937,8 @@ impl Clean<Type> for hir::Ty {
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}
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TyKind::BareFn(ref barefn) => BareFunction(box barefn.clean(cx)),
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TyKind::Infer | TyKind::Err => Infer,
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TyKind::Typeof(..) => panic!("Unimplemented type {:?}", self.node),
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TyKind::Typeof(..) => panic!("unimplemented type {:?}", self.node),
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TyKind::CVarArgs(_) => CVarArgs,
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TyKind::AssocTyExistential(ref bounds) => {
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ImplTrait(bounds.into_iter().map(|b| b.clean(cx)).collect())
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}
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}
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}
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}
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@ -3057,7 +3054,9 @@ impl<'tcx> Clean<Type> for Ty<'tcx> {
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for pb in obj.projection_bounds() {
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bindings.push(TypeBinding {
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name: cx.tcx.associated_item(pb.item_def_id()).ident.name.clean(cx),
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ty: pb.skip_binder().ty.clean(cx)
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kind: TypeBindingKind::Equality {
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ty: pb.skip_binder().ty.clean(cx)
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},
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});
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}
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@ -3113,7 +3112,9 @@ impl<'tcx> Clean<Type> for Ty<'tcx> {
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Some(TypeBinding {
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name: cx.tcx.associated_item(proj.projection_ty.item_def_id)
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.ident.name.clean(cx),
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ty: proj.ty.clean(cx),
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kind: TypeBindingKind::Equality {
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ty: proj.ty.clean(cx),
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},
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})
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} else {
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None
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@ -3498,7 +3499,7 @@ pub enum GenericArgs {
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impl Clean<GenericArgs> for hir::GenericArgs {
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fn clean(&self, cx: &DocContext<'_>) -> GenericArgs {
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if self.parenthesized {
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let output = self.bindings[0].ty.clean(cx);
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let output = self.bindings[0].ty().clean(cx);
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GenericArgs::Parenthesized {
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inputs: self.inputs().clean(cx),
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output: if output != Type::Tuple(Vec::new()) { Some(output) } else { None }
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@ -4346,18 +4347,53 @@ impl Clean<Deprecation> for attr::Deprecation {
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}
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}
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/// An equality constraint on an associated type, e.g., `A = Bar` in `Foo<A = Bar>`
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/// An type binding on an associated type (e.g., `A = Bar` in `Foo<A = Bar>` or
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/// `A: Send + Sync` in `Foo<A: Send + Sync>`).
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#[derive(Clone, PartialEq, Eq, RustcDecodable, RustcEncodable, Debug, Hash)]
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pub struct TypeBinding {
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pub name: String,
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pub ty: Type
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pub kind: TypeBindingKind,
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}
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#[derive(Clone, PartialEq, Eq, RustcDecodable, RustcEncodable, Debug, Hash)]
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pub enum TypeBindingKind {
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Equality {
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ty: Type,
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},
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Constraint {
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bounds: Vec<GenericBound>,
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},
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}
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impl TypeBinding {
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pub fn ty(&self) -> &Type {
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match self.kind {
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TypeBindingKind::Equality { ref ty } => ty,
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_ => panic!("expected equality type binding for parenthesized generic args"),
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}
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}
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}
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impl Clean<TypeBinding> for hir::TypeBinding {
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fn clean(&self, cx: &DocContext<'_>) -> TypeBinding {
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TypeBinding {
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name: self.ident.name.clean(cx),
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ty: self.ty.clean(cx)
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kind: self.kind.clean(cx),
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}
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}
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}
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impl Clean<TypeBindingKind> for hir::TypeBindingKind {
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fn clean(&self, cx: &DocContext<'_>) -> TypeBindingKind {
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||||
match *self {
|
||||
hir::TypeBindingKind::Equality { ref ty } =>
|
||||
TypeBindingKind::Equality {
|
||||
ty: ty.clean(cx),
|
||||
},
|
||||
hir::TypeBindingKind::Constraint { ref bounds } =>
|
||||
TypeBindingKind::Constraint {
|
||||
bounds: bounds.into_iter().map(|b| b.clean(cx)).collect(),
|
||||
},
|
||||
}
|
||||
}
|
||||
}
|
||||
|
@ -91,7 +91,9 @@ pub fn where_clauses(cx: &DocContext<'_>, clauses: Vec<WP>) -> Vec<WP> {
|
||||
PP::AngleBracketed { ref mut bindings, .. } => {
|
||||
bindings.push(clean::TypeBinding {
|
||||
name: name.clone(),
|
||||
ty: rhs.clone(),
|
||||
kind: clean::TypeBindingKind::Equality {
|
||||
ty: rhs.clone(),
|
||||
},
|
||||
});
|
||||
}
|
||||
PP::Parenthesized { ref mut output, .. } => {
|
||||
|
@ -1019,11 +1019,26 @@ impl fmt::Display for clean::ImportSource {
|
||||
|
||||
impl fmt::Display for clean::TypeBinding {
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
if f.alternate() {
|
||||
write!(f, "{} = {:#}", self.name, self.ty)
|
||||
} else {
|
||||
write!(f, "{} = {}", self.name, self.ty)
|
||||
f.write_str(&self.name)?;
|
||||
match self.kind {
|
||||
clean::TypeBindingKind::Equality { ref ty } => {
|
||||
if f.alternate() {
|
||||
write!(f, " = {:#}", ty)?;
|
||||
} else {
|
||||
write!(f, " = {}", ty)?;
|
||||
}
|
||||
}
|
||||
clean::TypeBindingKind::Constraint { ref bounds } => {
|
||||
if !bounds.is_empty() {
|
||||
if f.alternate() {
|
||||
write!(f, ": {:#}", GenericBounds(bounds))?;
|
||||
} else {
|
||||
write!(f, ": {}", GenericBounds(bounds))?;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
||||
|
Loading…
x
Reference in New Issue
Block a user