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alexreg/fails.rs

Created January 7, 2019 05:21
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`existential type` issue
Raw
fails.rs
trait TraitB {
type AssocB;
}
trait TraitC {
}
existential type Bar: Debug + TraitB<AssocB = impl Send>;
impl TraitB for i32 {
type AssocB = i32;
}
impl TraitC for i32 {
}
fn foo() -> Bar {
42
}
/*
GENERATED HIR (by `lower_existential_impl_trait` method)
Item { ident: Bar#0, id: NodeId(86), hir_id: HirId { owner: DefIndex(0:13), local_id: 0 }, attrs: [], node: Existential(ExistTy { generics: Generics { params: [], where_clause: WhereClause { id: NodeId(96), predicates: [] }, span: Span { lo: BytePos(0), hi: BytePos(0), ctxt: #0 } }, bounds: [Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(Debug), ref_id: NodeId(87), hir_ref_id: HirId { owner: DefIndex(0:13), local_id: 3 } }, span: Span { lo: BytePos(570), hi: BytePos(575), ctxt: #0 } }, None), Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(TraitB<AssocB = >), ref_id: NodeId(89), hir_ref_id: HirId { owner: DefIndex(0:13), local_id: 7 } }, span: Span { lo: BytePos(578), hi: BytePos(604), ctxt: #0 } }, None)], impl_trait_fn: None }), vis: Spanned { node: Inherited, span: Span { lo: BytePos(548), hi: BytePos(548), ctxt: #0 } }, span: Span { lo: BytePos(548), hi: BytePos(605), ctxt: #0 } }
Item { ident: #0, id: NodeId(93), hir_id: HirId { owner: DefIndex(1:14), local_id: 0 }, attrs: [], node: Existential(ExistTy { generics: Generics { params: [], where_clause: WhereClause { id: NodeId(283), predicates: [] }, span: Span { lo: BytePos(594), hi: BytePos(603), ctxt: #0 } }, bounds: [Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(Send), ref_id: NodeId(94), hir_ref_id: HirId { owner: DefIndex(1:14), local_id: 2 } }, span: Span { lo: BytePos(599), hi: BytePos(603), ctxt: #0 } }, None)], impl_trait_fn: None }), vis: Spanned { node: Inherited, span: Span { lo: BytePos(594), hi: BytePos(594), ctxt: #0 } }, span: Span { lo: BytePos(594), hi: BytePos(603), ctxt: #6 } }
TypeBinding { id: NodeId(91), ident: AssocB#0, ty: type(), span: Span { lo: BytePos(585), hi: BytePos(603), ctxt: #0 } }
*/
Raw
succeeds.rs
trait TraitB {
type AssocB;
}
trait TraitC {
}
existential type Bar: TraitB<AssocB = _0>;
existential type _0: Send;
impl TraitB for i32 {
type AssocB = i32;
}
impl TraitC for i32 {
}
fn foo() -> Bar {
42
}
/*
GENERATED HIR (by `lower_existential_impl_trait` method)
Item { ident: Bar#0, id: NodeId(86), hir_id: HirId { owner: DefIndex(0:13), local_id: 0 }, attrs: [], node: Existential(ExistTy { generics: Generics { params: [], where_clause: WhereClause { id: NodeId(94), predicates: [] }, span: Span { lo: BytePos(0), hi: BytePos(0), ctxt: #0 } }, bounds: [Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(Debug), ref_id: NodeId(87), hir_ref_id: HirId { owner: DefIndex(0:13), local_id: 3 } }, span: Span { lo: BytePos(631), hi: BytePos(636), ctxt: #0 } }, None), Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(TraitB<AssocB = _0>), ref_id: NodeId(89), hir_ref_id: HirId { owner: DefIndex(0:13), local_id: 8 } }, span: Span { lo: BytePos(639), hi: BytePos(658), ctxt: #0 } }, None)], impl_trait_fn: None }), vis: Spanned { node: Inherited, span: Span { lo: BytePos(609), hi: BytePos(609), ctxt: #0 } }, span: Span { lo: BytePos(609), hi: BytePos(659), ctxt: #0 } }
Item { ident: _0#0, id: NodeId(95), hir_id: HirId { owner: DefIndex(0:14), local_id: 0 }, attrs: [], node: Existential(ExistTy { generics: Generics { params: [], where_clause: WhereClause { id: NodeId(98), predicates: [] }, span: Span { lo: BytePos(0), hi: BytePos(0), ctxt: #0 } }, bounds: [Trait(PolyTraitRef { bound_generic_params: [], trait_ref: TraitRef { path: path(Send), ref_id: NodeId(96), hir_ref_id: HirId { owner: DefIndex(0:14), local_id: 3 } }, span: Span { lo: BytePos(681), hi: BytePos(685), ctxt: #0 } }, None)], impl_trait_fn: None }), vis: Spanned { node: Inherited, span: Span { lo: BytePos(660), hi: BytePos(660), ctxt: #0 } }, span: Span { lo: BytePos(660), hi: BytePos(686), ctxt: #0 } }
TypeBinding { id: NodeId(91), ident: AssocB#0, ty: type(_0), span: Span { lo: BytePos(646), hi: BytePos(657), ctxt: #0 } }
*/
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