diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/predicate.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/predicate.rs | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/compiler/rustc_middle/src/ty/predicate.rs b/compiler/rustc_middle/src/ty/predicate.rs index 7c5b49512ae..200811940ed 100644 --- a/compiler/rustc_middle/src/ty/predicate.rs +++ b/compiler/rustc_middle/src/ty/predicate.rs @@ -323,7 +323,7 @@ impl<'tcx> ty::List<ty::PolyExistentialPredicate<'tcx>> { /// and `U` as parameter 1. /// /// Trait references also appear in object types like `Foo<U>`, but in -/// that case the `Self` parameter is absent from the substitutions. +/// that case the `Self` parameter is absent from the generic parameters. #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, TyDecodable)] #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)] pub struct TraitRef<'tcx> { @@ -406,7 +406,7 @@ impl<'tcx> IntoDiagnosticArg for TraitRef<'tcx> { /// ```ignore (illustrative) /// exists T. T: Trait<'a, 'b, X, Y> /// ``` -/// The substitutions don't include the erased `Self`, only trait +/// The generic parameters don't include the erased `Self`, only trait /// type and lifetime parameters (`[X, Y]` and `['a, 'b]` above). #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, TyDecodable)] #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)] @@ -481,8 +481,8 @@ impl<'tcx> ExistentialProjection<'tcx> { /// reference. pub fn trait_ref(&self, tcx: TyCtxt<'tcx>) -> ty::ExistentialTraitRef<'tcx> { let def_id = tcx.parent(self.def_id); - let subst_count = tcx.generics_of(def_id).count() - 1; - let args = tcx.mk_args(&self.args[..subst_count]); + let args_count = tcx.generics_of(def_id).count() - 1; + let args = tcx.mk_args(&self.args[..args_count]); ty::ExistentialTraitRef { def_id, args } } @@ -534,12 +534,12 @@ impl<'tcx> PolyExistentialProjection<'tcx> { } impl<'tcx> Clause<'tcx> { - /// Performs a substitution suitable for going from a + /// Performs a instantiation suitable for going from a /// poly-trait-ref to supertraits that must hold if that /// poly-trait-ref holds. This is slightly different from a normal - /// substitution in terms of what happens with bound regions. See + /// instantiation in terms of what happens with bound regions. See /// lengthy comment below for details. - pub fn subst_supertrait( + pub fn instantiate_supertrait( self, tcx: TyCtxt<'tcx>, trait_ref: &ty::PolyTraitRef<'tcx>, @@ -556,7 +556,7 @@ impl<'tcx> Clause<'tcx> { // we can deduce that `for<'x> T: Bar<'x,'x>`. Basically, if we // knew that `Foo<'x>` (for any 'x) then we also know that // `Bar<'x,'x>` (for any 'x). This more-or-less falls out from - // normal substitution. + // normal instantiation. // // In terms of why this is sound, the idea is that whenever there // is an impl of `T:Foo<'a>`, it must show that `T:Bar<'a,'a>` @@ -582,7 +582,7 @@ impl<'tcx> Clause<'tcx> { // - We start out with `for<'x> T: Foo1<'x>`. In this case, `'x` // has a De Bruijn index of 1. We want to produce `for<'x,'b> T: Bar1<'x,'b>`, // where both `'x` and `'b` would have a DB index of 1. - // The substitution from the input trait-ref is therefore going to be + // The instantiation from the input trait-ref is therefore going to be // `'a => 'x` (where `'x` has a DB index of 1). // - The supertrait-ref is `for<'b> Bar1<'a,'b>`, where `'a` is an // early-bound parameter and `'b` is a late-bound parameter with a @@ -591,17 +591,17 @@ impl<'tcx> Clause<'tcx> { // a DB index of 1, and thus we'll have `for<'x,'b> Bar1<'x,'b>` // just as we wanted. // - // There is only one catch. If we just apply the substitution `'a - // => 'x` to `for<'b> Bar1<'a,'b>`, the substitution code will - // adjust the DB index because we substituting into a binder (it + // There is only one catch. If we just apply the instantiation `'a + // => 'x` to `for<'b> Bar1<'a,'b>`, the instantiation code will + // adjust the DB index because we instantiating into a binder (it // tries to be so smart...) resulting in `for<'x> for<'b> // Bar1<'x,'b>` (we have no syntax for this, so use your // imagination). Basically the 'x will have DB index of 2 and 'b // will have DB index of 1. Not quite what we want. So we apply - // the substitution to the *contents* of the trait reference, + // the instantiation to the *contents* of the trait reference, // rather than the trait reference itself (put another way, the - // substitution code expects equal binding levels in the values - // from the substitution and the value being substituted into, and + // instantiation code expects equal binding levels in the values + // from the instantiation and the value being instantiated into, and // this trick achieves that). // Working through the second example: |