2 files changed, 40 insertions, 40 deletions

diff --git a/crates/hir_ty/src/traits/chalk.rs b/crates/hir_ty/src/traits/chalk.rs
index b7388b98c..dff87ef70 100644
--- a/crates/hir_ty/src/traits/chalk.rs
+++ b/crates/hir_ty/src/traits/chalk.rs
@@ -184,16 +184,21 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
                     .db
                     .return_type_impl_traits(func)
                     .expect("impl trait id without impl traits");
-                let data = &datas.value.impl_traits[idx as usize];
+                let (datas, binders) = (*datas).as_ref().into_value_and_skipped_binders();
+                let data = &datas.impl_traits[idx as usize];
                 let bound = OpaqueTyDatumBound {
                     bounds: make_binders(
-                        data.bounds.value.iter().cloned().map(|b| b.to_chalk(self.db)).collect(),
+                        data.bounds
+                            .skip_binders()
+                            .iter()
+                            .cloned()
+                            .map(|b| b.to_chalk(self.db))
+                            .collect(),
                         1,
                     ),
                     where_clauses: make_binders(vec![], 0),
                 };
-                let num_vars = datas.num_binders;
-                make_binders(bound, num_vars)
+                chalk_ir::Binders::new(binders, bound)
             }
             crate::ImplTraitId::AsyncBlockTypeImplTrait(..) => {
                 if let Some((future_trait, future_output)) = self
@@ -535,7 +540,8 @@ fn impl_def_datum(
         .impl_trait(impl_id)
         // ImplIds for impls where the trait ref can't be resolved should never reach Chalk
         .expect("invalid impl passed to Chalk")
-        .value;
+        .into_value_and_skipped_binders()
+        .0;
     let impl_data = db.impl_data(impl_id);
 
     let generic_params = generics(db.upcast(), impl_id.into());
@@ -605,18 +611,22 @@ fn type_alias_associated_ty_value(
         _ => panic!("assoc ty value should be in impl"),
     };
 
-    let trait_ref = db.impl_trait(impl_id).expect("assoc ty value should not exist").value; // we don't return any assoc ty values if the impl'd trait can't be resolved
+    let trait_ref = db
+        .impl_trait(impl_id)
+        .expect("assoc ty value should not exist")
+        .into_value_and_skipped_binders()
+        .0; // we don't return any assoc ty values if the impl'd trait can't be resolved
 
     let assoc_ty = db
         .trait_data(trait_ref.hir_trait_id())
         .associated_type_by_name(&type_alias_data.name)
         .expect("assoc ty value should not exist"); // validated when building the impl data as well
-    let ty = db.ty(type_alias.into());
-    let value_bound = rust_ir::AssociatedTyValueBound { ty: ty.value.to_chalk(db) };
+    let (ty, binders) = db.ty(type_alias.into()).into_value_and_skipped_binders();
+    let value_bound = rust_ir::AssociatedTyValueBound { ty: ty.to_chalk(db) };
     let value = rust_ir::AssociatedTyValue {
         impl_id: impl_id.to_chalk(db),
         associated_ty_id: to_assoc_type_id(assoc_ty),
-        value: make_binders(value_bound, ty.num_binders),
+        value: chalk_ir::Binders::new(binders, value_bound),
     };
     Arc::new(value)
 }
@@ -628,20 +638,15 @@ pub(crate) fn fn_def_datum_query(
 ) -> Arc<FnDefDatum> {
     let callable_def: CallableDefId = from_chalk(db, fn_def_id);
     let generic_params = generics(db.upcast(), callable_def.into());
-    let sig = db.callable_item_signature(callable_def);
+    let (sig, binders) = db.callable_item_signature(callable_def).into_value_and_skipped_binders();
     let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
     let where_clauses = convert_where_clauses(db, callable_def.into(), &bound_vars);
     let bound = rust_ir::FnDefDatumBound {
         // Note: Chalk doesn't actually use this information yet as far as I am aware, but we provide it anyway
         inputs_and_output: make_binders(
             rust_ir::FnDefInputsAndOutputDatum {
-                argument_types: sig
-                    .value
-                    .params()
-                    .iter()
-                    .map(|ty| ty.clone().to_chalk(db))
-                    .collect(),
-                return_type: sig.value.ret().clone().to_chalk(db),
+                argument_types: sig.params().iter().map(|ty| ty.clone().to_chalk(db)).collect(),
+                return_type: sig.ret().clone().to_chalk(db),
             }
             .shifted_in(&Interner),
             0,
@@ -650,12 +655,8 @@ pub(crate) fn fn_def_datum_query(
     };
     let datum = FnDefDatum {
         id: fn_def_id,
-        sig: chalk_ir::FnSig {
-            abi: (),
-            safety: chalk_ir::Safety::Safe,
-            variadic: sig.value.is_varargs,
-        },
-        binders: make_binders(bound, sig.num_binders),
+        sig: chalk_ir::FnSig { abi: (), safety: chalk_ir::Safety::Safe, variadic: sig.is_varargs },
+        binders: chalk_ir::Binders::new(binders, bound),
     };
     Arc::new(datum)
 }
diff --git a/crates/hir_ty/src/traits/chalk/mapping.rs b/crates/hir_ty/src/traits/chalk/mapping.rs
index 67e88ebf4..c3b148cab 100644
--- a/crates/hir_ty/src/traits/chalk/mapping.rs
+++ b/crates/hir_ty/src/traits/chalk/mapping.rs
@@ -93,12 +93,13 @@ impl ToChalk for Ty {
             TyKind::BoundVar(idx) => chalk_ir::TyKind::BoundVar(idx).intern(&Interner),
             TyKind::InferenceVar(..) => panic!("uncanonicalized infer ty"),
             TyKind::Dyn(dyn_ty) => {
+                let (bounds, binders) = dyn_ty.bounds.into_value_and_skipped_binders();
                 let where_clauses = chalk_ir::QuantifiedWhereClauses::from_iter(
                     &Interner,
-                    dyn_ty.bounds.value.interned().iter().cloned().map(|p| p.to_chalk(db)),
+                    bounds.interned().iter().cloned().map(|p| p.to_chalk(db)),
                 );
                 let bounded_ty = chalk_ir::DynTy {
-                    bounds: make_binders(where_clauses, 1),
+                    bounds: chalk_ir::Binders::new(binders, where_clauses),
                     lifetime: LifetimeData::Static.intern(&Interner),
                 };
                 chalk_ir::TyKind::Dyn(bounded_ty).intern(&Interner)
@@ -148,7 +149,7 @@ impl ToChalk for Ty {
                     .map(|c| from_chalk(db, c.clone()));
                 TyKind::Dyn(crate::DynTy {
                     bounds: crate::Binders::new(
-                        1,
+                        where_clauses.bounds.binders.clone(),
                         crate::QuantifiedWhereClauses::from_iter(&Interner, bounds),
                     ),
                 })
@@ -486,19 +487,13 @@ where
     type Chalk = chalk_ir::Binders<T::Chalk>;
 
     fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Binders<T::Chalk> {
-        chalk_ir::Binders::new(
-            chalk_ir::VariableKinds::from_iter(
-                &Interner,
-                std::iter::repeat(chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General))
-                    .take(self.num_binders),
-            ),
-            self.value.to_chalk(db),
-        )
+        let (value, binders) = self.into_value_and_skipped_binders();
+        chalk_ir::Binders::new(binders, value.to_chalk(db))
     }
 
     fn from_chalk(db: &dyn HirDatabase, binders: chalk_ir::Binders<T::Chalk>) -> crate::Binders<T> {
         let (v, b) = binders.into_value_and_skipped_binders();
-        crate::Binders::new(b.len(&Interner), from_chalk(db, v))
+        crate::Binders::new(b, from_chalk(db, v))
     }
 }
 
@@ -524,7 +519,7 @@ pub(super) fn convert_where_clauses(
     let generic_predicates = db.generic_predicates(def);
     let mut result = Vec::with_capacity(generic_predicates.len());
     for pred in generic_predicates.iter() {
-        result.push(pred.clone().subst(substs).to_chalk(db));
+        result.push(pred.clone().substitute(&Interner, substs).to_chalk(db));
     }
     result
 }
@@ -536,8 +531,9 @@ pub(super) fn generic_predicate_to_inline_bound(
 ) -> Option<chalk_ir::Binders<rust_ir::InlineBound<Interner>>> {
     // An InlineBound is like a GenericPredicate, except the self type is left out.
     // We don't have a special type for this, but Chalk does.
-    let self_ty_shifted_in = self_ty.clone().shift_bound_vars(DebruijnIndex::ONE);
-    match &pred.value {
+    let self_ty_shifted_in = self_ty.clone().shifted_in_from(DebruijnIndex::ONE);
+    let (pred, binders) = pred.as_ref().into_value_and_skipped_binders();
+    match pred {
         WhereClause::Implemented(trait_ref) => {
             if trait_ref.self_type_parameter(&Interner) != &self_ty_shifted_in {
                 // we can only convert predicates back to type bounds if they
@@ -549,7 +545,7 @@ pub(super) fn generic_predicate_to_inline_bound(
                 .map(|ty| ty.clone().to_chalk(db).cast(&Interner))
                 .collect();
             let trait_bound = rust_ir::TraitBound { trait_id: trait_ref.trait_id, args_no_self };
-            Some(make_binders(rust_ir::InlineBound::TraitBound(trait_bound), pred.num_binders))
+            Some(chalk_ir::Binders::new(binders, rust_ir::InlineBound::TraitBound(trait_bound)))
         }
         WhereClause::AliasEq(AliasEq { alias: AliasTy::Projection(projection_ty), ty }) => {
             if projection_ty.self_type_parameter(&Interner) != &self_ty_shifted_in {
@@ -566,7 +562,10 @@ pub(super) fn generic_predicate_to_inline_bound(
                 associated_ty_id: projection_ty.associated_ty_id,
                 parameters: Vec::new(), // FIXME we don't support generic associated types yet
             };
-            Some(make_binders(rust_ir::InlineBound::AliasEqBound(alias_eq_bound), pred.num_binders))
+            Some(chalk_ir::Binders::new(
+                binders,
+                rust_ir::InlineBound::AliasEqBound(alias_eq_bound),
+            ))
         }
         _ => None,
     }